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(The Wargame of the Century)

Written by Walter Bright
Copyright (c) 1982-2001 by Walter Bright
All Rights Reserved

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This software is furnished under a license for use only by the purchaser. This software may not be copied or made available to any other persons. Title and ownership of the software shall remain at all times in Northwest Software.

Northwest Software assumes no liability for the use or misuse of its software. Liability for any warranties implied or stated is limited to the replacement of the distribution floppy disk should it be determined to be defective within thirty days of its purchase.


Congratulations! You have purchased one of the most popular games on mainframe computers, now made available on the personal computer. Empire was originally written by Walter Bright for a PDP-10 at Caltech. The game has since been converted to run on a DEC VAX, and has been played for years at Caltech, MIT and at VAX installations. Empire was rewritten from scratch to run on smaller computers.

Empire is a simulation of a global conflict between two to three implacable foes. No compromise is possible, each must strive to annihilate the other. The war is conducted over a large map, with land, sea and cities on it. Each player manipulates his armies, fighters and ships to try and smash the others, to reach the goal of total domination of the world. Empire is not a video arcade-type game. It is a thinking man's game, as it requires strategy and tactics instead of hand-eye coordination.

Warning: Empire has been known to be addictive. Typical games can take several hours.


The following hardware and software is required to run IBM PC Empire:
  • 8088 or 8086 based computer (such as IBM PC or XT).
  • PC-DOS or MS-DOS version 1.1 or later.
  • 5 1/4" floppy disk drive capable of reading MS-DOS format floppy disks.
  • 128kb of memory.
  • IBM monochrome display adapter with IBM monochrome display.


    IBM color display adapter with color or b/w display.


    One of the following terminals as the console device:

    • ANSI Standard compatible
    • DEC VT100
    • DEC VT52
    • Heath/Zenith H19/Z19
    • Lear Siegler ADM-3A (capable of lower case)
    • ADDS Viewpoint
    • Televideo 925
    • Hazeltine 1500
  • An extra serial port and terminal for each additional live player desired (2 maximum).
  • EMPIRE distribution floppy with the following files on it:
              EMPIRE.EXE     EMPIRE2.EXE    (backup copies)
              A.MAP          A2.MAP
              B.MAP          B2.MAP


Perform the following steps to get EMPIRE running on your computer:
  1. Follow your computer's instructions to boot up MS-DOS.
  2. Make a backup copy of your EMPIRE distribution disk. (EMPIRE is copyrighted, but is not copy-protected, so you can make backups (for your personal use only) using the normal MS-DOS copy command.)
  3. Place your EMPIRE distribution disk in the default drive.
  4. Type EMPIRE. The drive light will come on for a few seconds, after which this will appear on your display:
        Empire version x.x
        Copyright (c) 1983, 1984 by Northwest Software
        Written by Walter Bright
        Do you want the speaker turned on (Y or N)? N
  5. Press the Y key if you would like sound. Press N or RETURN if not. Note: Press N if you are not running EMPIRE on an IBM PC.
  6. Now you will see (if you have previously saved a game):
        Continuing a previous game (Y or N)? N
    Press the RETURN key if you are not, press Y if you are. If you restored a previous game, you are now back where you were when you saved it. Otherwise, follow on. Note: games are saved in a file called EMPIRE.DAT on the default drive. If it is not there, this step will be skipped.
  7. EMPIRE will ask how many players are playing. Two or three can play, but you can designate the computer to run any or all of the players if you don't have someone to play against. Note that you will need an extra serial port and terminal for each human opponent.
  8. Now come a series of questions about each player. You must decide for each player whether he is real or is played by the computer, and what he has for a display (computer players don't need a display).
  9. If you select a player to play off of com1: or com2:, you must have these serial ports installed and a terminal attached to them. The characteristics of com1: and com2: must also have been set up prior to running EMPIRE by using the MS-DOS MODE command. There is more information about setting up the serial ports at the end of this booklet.
  10. The display option 'Conform to MS-DOS protocol' is used when you are running MS-DOS from a terminal. This option is also useful if your machine does not have IBM PC compatible display hardware, but can emulate a terminal.
  11. Computer players can be set to 'No display'. Use this option if you don't have a com1: or com2: to display them on.
  12. If you specified all the players to be run by the computer, EMPIRE will now run until somebody wins or you turn off the power.
  13. For each human player, you will be asked for your initial city production demands. Press one of the following keys selecting what you want your city to produce:
    A: Armies
    F: Fighters
    D: Destroyers
    T: Troop transports
    S: Submarines
    R: Cruisers
    C: Aircraft carriers
    B: Battleships
    For your first game, pressing A for armies is recommended.
  14. You're off and running! Please refer to the OPERATION section for how to play the game.


The game is played on a map of 60 rows by 100 columns. Row numbers are 0 to 59, column numbers are 0 to 99. Coordinates are shown as row,col.

Characters displayed on the map are (for terminals):

blank unknown territory
. sea
+ land
* unconquered city
Player 1:
O conquered city
A army
F fighter
D destroyer
T troop transport
S submarine
R cruiser
C aircraft carrier
B battleship
Player 2:
o conquered city
a army
f fighter
d destroyer
t troop transport
s submarine
r cruiser
c aircraft carrier
b battleship
Player 3:
X conquered city
1 army
2 fighter
3 destroyer
4 troop transport
5 submarine
6 cruiser
7 aircraft carrier
8 battleship
The display is the same for the IBM monochrome display, except that the land is shown as a block. For the color display, OAFDTSRCB is used for each player, but Player 1 is yellow, Player 2 is red and Player 3 is purple. Also, the land is green, the sea is blue and unconquered cities are black.

The entire map is unknown (blank) until you start to explore it. Beware, however, that you cannot detect enemy pieces unless you are right next to them. The actual map that you see on the display is a summary of all the most recent information that you have about the world.

Each of your cities can be assigned to produce one of the pieces (A,F,D,T,S,R, C or B). A city is attacked by moving an army onto it. The army has a 50% chance of conquering it. Capturing cities is crucial to destroying your opponents.

An enemy piece is attacked by moving one of your pieces onto it. Hits are traded off (at a 50% chance of landing on one piece or the other) until one piece is totally destroyed. Only one of the pieces will survive the conflict. Each piece can withstand only so many hits before it is destroyed. Damage sustained by a piece is cumulative until it is either destroyed or repaired. The number of hits that each piece can take are:

          army                1
          fighter             1
          destroyer           3
          troop transport     3
          submarine           2
          cruiser             8
          aircraft carrier    8
          battleship          12
Ships can be repaired by moving them into one of your cities.


Armies are of primary importance. Only armies can capture cities and take over continents. They move on land at a rate of 1 move per round. Movement across water is performed using a troop transport. To board a troop transport, just move your army onto it. Armies cannot move onto their own cities, they will be destroyed if they try. Armies drown when moving across water without the aid of a troop transport.
Fighters are airplanes that can move over land or sea at the rate of 4 moves per round. They have a limited range, however, of 20 moves before they must refuel. Fighters can refuel by landing in conquered cities or on one of your aircraft carriers. Attempting to land in cities that aren't yours is futile.
Destroyers, Cruisers, Battleships:
Ships can move on sea, or can dock in captured cities. They move at 2 moves per round like all ships, unless they're heavily damaged. In this case movement drops to 1 move per round. Ships can be repaired by docking them (moving them into one of your cities). These ships are normally used to protect your own troop transports or to menace the enemy's. Ships run aground and sink if you move them onto dry land.
Submarines are like the other ships except that if one should score a hit against an enemy ship, 3 hits worth of damage is done instead of 1 (enough to sink the smaller ships!).
Troop Transports:
Troop transports are used to carry armies from one continent to another. They can carry up to 6 armies, less if they're damaged. Troop transport captains are very short-tempered and tend to deal abruptly with armies should too many get aboard.
Aircraft Carriers:
Carriers can carry and refuel fighters. They can carry a maximum of 8, less if they're damaged.


The program will prompt you to move each piece. The prompt consists of a short message in the upper left corner of the screen, and the cursor will be positioned on the map. The message shows what mode you are in. The modes are:
  • Move
  • Survey
  • Direction
  • From To
  • City Prod
If no mode message is displayed, the program is not expecting a command. All commands consist of single keys. No carriage return is required.

Direction keys:

    A D        This is the layout of the direction keys
    ZXC        on a QWERTY keyboard.
The letters QWEADZXC represent directions of movement, as if the cursor were situated on the letter S of your keyboard. For example, E means move upward and to the right. X means move straight down. The space bar indicates no movement.

If you have an IBM PC keyboard, the arrow keys may be used instead.

Each mode is explained below.


Most of the game will be spent in move mode. In fact, the entire game can be played without ever leaving it. In this mode, the cursor will be positioned over where the piece is, and the top line of the display will show what the piece is. You can enter either a move or a command.

A move is entered by pressing one of the direction keys indicating the direction that you want the piece to go in. If you don't want the piece to move, press the space bar.

The following commands are available in MOVE mode:

Set the piece to move towards a specified location. This will put you in the From To mode. See FUNCTIONS.
Set the piece (must be a fighter) moving towards the nearest owned city or aircraft carrier.
Give the enemy 20 free moves. Do this if you feel the enemy is doing poorly and is not giving you a sufficient challenge.
Set the piece to moving in a specified direction. This will put you in the Direction mode. See FUNCTIONS.
Turn the sound on/off.
Awaken the piece the cursor is on. See FUNCTIONS.
Set the piece (a troop transport or aircraft carrier) in the Load Armies or Load Fighters function. See FUNCTIONS.
Center the screen about the current position of the cursor.
Set the piece to moving at random. See FUNCTIONS.
Set the piece to be a sentry. See FUNCTIONS.
If the piece is a troop transport or an aircraft carrier, wake up all the armies or fighters that are aboard.
Save the game. The game will be saved in a file called EMPIRE.DAT on the default drive. The file will be 31000 bytes long. If your disk is too full for it, you will get an error mesasge. If so, insert an empty (but formatted) disk in and try again.
Enter SURVEY mode.
Control Break
This is used to exit the program and return to DOS.
Decrease delay time by 1/4 second. This delay time is the time that messages stay on the screen before the program moves on. The messages become redundant after a while, and can be speeded up with this command.
Increase delay time by 1/4 second. Use if the messages flash by too fast.


This mode allows you to travel around and look at the map, alter the functions assigned to your pieces, change the production demands given to cities, etc. It is entered using the Y command from MOVE mode.

The direction keys move the cursor around. Each time you move the cursor onto one of your pieces or cities, information on that piece or city will be displayed. Note that commands in SURVEY mode operate only on the piece displayed (for instance, you cannot operate on an army aboard a troop transport from the SURVEY mode).

Most commands operate the same as in move mode. The differences are:

Using G when the cursor is on a city sets the FIPATH of that city to the nearest conquered city or aircraft carrier. See FIPATH.
Using K when the cursor is on a city disables the city's FIPATH if it has one. See FIPATH.
Assign new production demands to a city by putting you in the CITY PROD mode.
Using U when the cursor is on a city awakens all the pieces that may be in that city.
Not available.
Return to MOVE mode.


This mode expects a direction key to be pressed. This will then assign the direction function to the piece that the cursor is on. See FUNCTIONS.

Escape (the esc key) will abort this mode.


This mode expects a key representing what you demand that your city produce be pressed. The keys are:
                                 Production Time

                        Key      Start    Continue
    armies               A         6         5
    fighters             F         12        10
    destroyers           D         24        20
    troop transports     T         36        30
    submarines           S         30        25
    cruisers             R         60        50
    aircraft carriers    C         72        60
    battleships          B         90        75
The start time is the number of rounds required to produce a piece for the first time. The continuing time is the number of rounds required to produce subsequent pieces. If you change the production demands of a city before it has completed its piece, the partially completed piece will be discarded.


This mode is used to assign the MOVE TO function to a piece. Move the cursor until it is on the location that you wish to move the piece to, and press T (as in FROM location TO location).

Note: If you are giving the MOVE TO function to a fighter, the cursor's distance from the fighter cannot exceed the fighter's fuel remaining. This also applies to setting the FIPATH of a city.

Escape will abort this mode.


In order to relieve the tedium of moving each piece each round, your pieces can be assigned various functions, under which they move automatically. The functions are:
No function, or awake. You will be asked for a move each turn.
The piece will not move.
The piece will move at random subject to the following conditions:
  1. The piece will not do anything to cause it to be destroyed.
  2. If it is an army, it will board an unloaded troop transport and wake up if it is next to one.
The piece is set to move towards a specified location. When it arrives, it will return to the NONE function. If something is in the way, you will be asked to move the piece around the obstacle (this is called temporarilly waking up).
The piece will move in a specified direction. It will temporarilly wake up if something is in its way.
A troop transport can be assigned this function, in which case it will go on sentry duty until it is fully loaded with armies.
Same as LOAD ARMIES, but for aircraft carriers instead.
In general, the following constraints apply:
  1. When a fighter is 10 moves out, it will temporarilly wake up to give you a chance to return it to a city or carrier for refueling. The G command comes in handy here.
  2. Armies always temporarilly wake up if they're next to an unconquered city.
  3. All pieces wake up if they're next to an enemy piece.


Each of your cities can be assigned a FIPATH. This is a location, which when a fighter lands in that city, is assigned to that fighter. It shows up as a MOVE TO function for the fighter. FIPATHS are assigned to cities from the SURVEY mode using the F and T commands. Clear the FIPATH using the K command. FIPATHs are very useful when cities are producing fighters far from the front, the fighters can be 'chained' from city to city up to the front.


Other players' moves are performed while the computer is waiting for a command from you. This can be entertaining at times, like when a piece is destroyed while you are trying to move it! In any case, there is a 10 to 20 round maximum spread between players. If you exceed this limit, no more commands will be accepted until the other players have caught up a bit.

Watch out on the map displays. The locations of enemy pieces shown may not be accurate, as they probably moved since you detected them! Remember that the map displays only a history of what you have seen before.

If the message OVERPOP should appear, the game is saturated with too many pieces. No more will be produced until some are destroyed.

The computer operated players play by the same rules and under the same conditions that you do. It has no special advantages, though it may appear otherwise at times.

When a new game is started, it may take 100 to 200 rounds of play before you discover the other players (or they discover you!). Be patient, it's a large map.

Be careful of whether you are in MOVE mode or SURVEY mode. Entering many commands in MOVE mode when you thought you were in SURVEY mode can run ships aground and drown armies inadvertantly.

When in MOVE mode, and the cursor is on a troop transport, the message at the top of the screen will show whether a transport is to be moved or an army that is aboard it. Moving the wrong one can run the transport aground or drown the army.


Setting up the serial ports to work with another terminal can be confusing and frustrating. Here is a scheme which should work in most cases (Northwest Software does not guarantee that it will work).

Wire up an interconnecting cable as shown:

     pin              pin
        |            |
      7-+            +-7



      4-+            +-4
        |            |
      5-+            +-5
        |            |
      8-+            +-8

      6-+            +-6
        |            |
     20-+            +-2
Set up the serial port with the following command:
          mode com1:96,n,8,1
which sets it up to 9600 baud, no parity, 8 data bits, 1 stop bit. Set up the terminal to match. The connection can be verified by typing:
          copy con: com1:
Type a few characters on the PC, ending with a few ^Zs and RETURNs. The characters should show up on the terminal. To check communications the other way, type:
          copy com1: con:
And type a few characters on the terminal, ending with a few ^Zs and RETURNs. The characters should show up on the console. If these checks work, then EMPIRE should.

EMPIRE for Windows 95, 98, NT, 2000 and XP

EMPIRE is now a 32 bit program. It behaves a little differently under Win32:
  • Only one human player is allowed, but up to 5 computer driven opponents are possible.
  • The one human play is played in a console window.
  • To open a console window, click on the [MSDOS] icon. For Windows XP, click on the [Command Prompt] from the [Start] Menu.
  • It is possible to adjust the console window size to show the entire map at once without scrolling. To do so:
    1. Click on the [MSDOS] icon in the upper left corner of the console window.
    2. Click on [Properties...]
    3. Click on [Layout]
    4. Under [Screen Buffer Size], select a width of 102 and a height of 65.
    5. Click [OK]
    6. Select [Apply properties to current window only]
    7. Click [OK]
    If unwanted scroll bars appear, try a smaller font:
    1. Click on the [MSDOS] icon in the upper left corner of the console window.
    2. Click on [Properties...]
    3. Click on [Font]
    4. Select [8 x 8] font.
    5. Click [OK]
    6. Select [Apply properties to current window only]
    7. Click [OK]
  • EMPIRE has the following command line switches:
    Run in demo mode, which means the computer plays itself. This is the default.
    Cause EMPIRE to be run at a background priority.
    Select number of players, where n is 2 to 6. The default is 6.