Philippe Thibaut and Lewis Pulsipher (designers). Mar 2022

This is a game of invasions and survival. Each player (four, human or AI-driven) controls 4 or 5 nations, each nation has different objectives. The player whose nations score the most points by the end of 16 Rounds wins. The rules may seem initially complex, but the game is easy to play in practice, nearly as easy as Risk, easier than Axis and Allies. The game covers the period from the Roman invasion to the Norman invasion, over 1,000 years.

Objective: Score points, mostly from holding territory, as shown on Nation windows. Most points for your nations at the end of the game wins. With a few exceptions, nations all score at the end of Turns 5, 7, 10, 13 and 16. Victory Points are presented in a summary window at the end of each turn for easier follow-up (none are secret)

Invasions Series - Britannia
Phases

Sequence: Each nation (not player) plays in turn.
1) Get population increase and scheduled reinforcements (shown on the mapboard);
2) move units;
3) fight.
When all nations have played the turn is over.

Increase of Population: Count 2 for each clear terrain region, 1 for difficult; 6 points earns a new army, any remainder is saved (up to 5 points). Purchases are mandatory.

Movement: Two areas, three if cavalry, or Romans, or with a leader; opponent stops movement unless you outnumber defenders 2-1 (“overrun”); those not needed to overrun can continue move. Difficult terrain halts movement unless a leader is moving along with the armies.
No more than two of your armies can be in a difficult terrain area, or three in non-difficult (clear), except you are allowed one “overstack”, which can be up to four in difficult, unlimited in clear.

Combat: When jointly occupying a region after movement is done, both sides simultaneously roll 6-sided dice, one per army, eliminating an opponent with a roll of 5 or 6. Cavalry and Romans need 4, 5, or 6 to hit in clear terrain. A 6 is needed to kill defenders in difficult terrain, cavalry, or Romans. After all armies in an area have fought once, the defender, then attacker, can retreat one or more armies. Fight until only one side remains in the region.

Leaders: allow movement through difficult terrain; up to three areas; and add one to combat dice rolls. A given leader is in the game only one turn, except at the end of the game during turns 15 and 16 (the “Four Kings” period).

Raiders: may go back to sea after all combat has ended; they may an adjacent retreat to sea during combat.

Invaders: usually come over the sea, sometimes have Major Invasion (Increase, move, fight, move, fight).

Overpopulation: At the end of your turn you cannot have more than twice as many armies as the number of regions you occupy.

Invasions - Britannia
Vikings

The Romans are exceptions to many rules: they have “roads” (in Fort or Vassal regions) that aid movement, they build forts (that can be burned down by attackers, in which case they lose their benefits and cannot be rebuilt), they can have large stacks everywhere and overpopulation, and they leave at the end of Turn 5 and are succeeded by Romano-British.
Some nations can submit to Romans in order to survive.

The game goes through different eras: Roman conquest, the triumph of the English, the Vikings, and the “Four Kings”. Different nations and colors are most dominant in each era. It is not a conquest game in Risk style; you can play it that way, but you probably won’t win. The strategy is deep, every move, every location, matters. No one is going to recognize most of the ramifications until they have played several times. I know people who have played five hundred times (counting original Brit), yet still enjoy the strategy.

Britannia is an epic game, 2-4 hours for experienced players. There are shorter scenarios included for those who have less time.