Short answers, pulled from the story.
Defender of the Fatherland Day is a holiday observed in Russia, Turkmenistan, Belarus, Kyrgyzstan, Kazakhstan and Tajikistan that honors each country's armed forces and commemorates the founding of the Red Army.
It falls on the 23rd of February in most of the countries that observe it, though Kazakhstan celebrates on the 7th of May and Turkmenistan marks its version on the 27th of January.
The holiday has been renamed several times: it began as Red Army Day in 1919, became Day of the Red Army and the Navy in 1923, Soviet Army and Navy Day in 1949, and received its current name from President Vladimir Putin in 2002.
In Russia, the holiday unofficially doubles as a nationwide celebration of men, functioning as a counterpart to International Women's Day on the 8th of March. Women give small gifts to husbands, fathers, sons, brothers and coworkers, which is why the day is colloquially called Men's Day.
Ukraine abolished the holiday in 1992 and never restored it as a state holiday. President Petro Poroshenko later said Ukraine should honor its own defenders rather than Russia's military-historical calendar, and a decree on the 14th of October 2014 created Defender of Ukraine Day, celebrated on the 1st of October, in its place.
It is marked as a public holiday in the unrecognized state of Transnistria, centered on celebrations in Tiraspol, and in the partially recognized Republic of South Ossetia, where the 23rd of February honors veterans of the Soviet Army and those who died in the 1991-1992 South Ossetia War and the Russo-Georgian War.