1

mass conversions

2

an earthquake

3

an age of exploration

4

a terrible famine

5

a disastrous flood

6

a legendary storm

7

an assassination

8

a series of riots

9

a great discovery

10

a vermin infestation

11

a destructive fire

12

a deadly plague

13

a bloody rebellion

14

a lengthy siege

15

religious wars

16

territorial wars

17

a foreign occupation

18

an economic boom

19

a great depression

20

a dragon attack