Did any countries change sides in World War 1?

Yes, during World War I, several countries changed sides. Notably, Italy switched from the Triple Alliance with Germany and Austria-Hungary to join the Allies in 1915, motivated by territorial promises. Additionally, in 1918, the newly formed state of Finland, which had previously been part of the Russian Empire, aligned itself with Germany before ultimately declaring independence. These shifts reflected the complex political dynamics and shifting alliances of the war.