Fortification work in the Karelian Isthmus at the border with the Soviet Union begins on a voluntary basis.
A delegation headed by J. K. Paasikivi leaves for Moscow to discuss the Soviet Union’s territorial claims.
The reservists are called to extra refresher training, which in practice means mobilisation of the Finnish army.
The Soviet-Finnish negotiations in Moscow fail.
The Soviet Union attacks Finland, starting the Winter War. Helsinki and several other cities in Finland are bombed.