Here is the full list of all 51 Grand Ages: Medieval trophies - there are 38 bronze, 10 silver, 2 gold and 1 platinum.
All trophies received
Finished first multiplayer game
Won first multiplayer game
Snuffed out a fellow player's troop
Took over a fellow player's town
Handed goods over to a fellow player
Out of all your competitors, you founded the most towns upon reaching the rank of "Emperor".
Out of all your competitors, you built the most businesses upon reaching the rank of "Emperor".
You have recruited 100 troops in the game.
Out of all your competitors, you had the largest town or city upon reaching the rank of "Emperor".
Recruited a troop of knights
5 towns taken over by diplomatic means
Campaign: You have completed the campaign
You have built 10,000 km of roads.
Campaign: Barnas Goes Nuts
5 towns taken over by military means
You have declared war.
6 towns taken over
You have built 10 defense towers.
A town has reached 15,000 inhabitants
A town has reached 8,000 inhabitants
You have destroyed 5 bandit camps.
Campaign: In bed with Eudokia
You have built your first ship
You have eliminated a competitor.
4 towns taken over
You have plundered 50 traders.
You have plundered 10 traders.
2 towns taken over
You have built 500 businesses.
You have 50 units of military troops under your command
12 towns founded
You have discovered 50 Adventure Sites.
You have slain 5 predators.
You have unlocked an entire tree in the development diagram.
8 towns founded
You have celebrated your first festival.
You have amassed 50,000,000 gold.
You have traded 1,000,000 barrels of commodities.
You have amassed 5,000,000 gold.
You have built 200 businesses.
A town has reached 3,000 inhabitants
You have unlocked all commodities.
You have built 50 businesses.
4 towns founded
One of your towns or cities has achieved the maximum level of prosperity.
You have built 1,000 km of roads.
You have traded 10,000 barrels of commodities.
You have discovered 10 Adventure Sites.
You have maximized the experience of a military troop.
You have entered into your first trade agreement.