San Marino formally declared war on Germany in 1944 after Germany stationed troops there due to it being mistakenly Bombed by Britain.
Costa Rica had a brutal civil war known as the Ochomongo War, and a few years later held a National Campaign to kill someone known as William Walker.
Iceland had a brutal volcanic eruption wiping out 50% of crops and 20% of the entire island population.
Liechtenstein faced the flood of the Rhine, which submerged tens of thousands of livestock, while drowning and starving the people living in it.