Short answers, pulled from the story.
The Football Federation of what was then the Kingdom of Serbs, Croats and Slovenes founded itself in Zagreb during 1919. Jovan Ružić became the first Serb to represent the national team in its international debut match at the 1920 Olympic Games in Antwerp.
Dušan Tadić stands as Serbia's most-capped player with 111 appearances between 2008 and 2024 scoring 23 goals. Branislav Ivanović follows with 105 caps and 13 goals while Aleksandar Mitrović has 104 caps and 63 goals making him top scorer.
The national team ceased activities during World War II but reformed following the end of hostilities. The Federal Republic of Yugoslavia formed on the 27th of April 1992 with teams banned from all international sporting events due to U.N. sanctions stemming from conflict in Yugoslavia.
On the 3rd of June 2006 following a referendum Montenegro declared its independence leading to separate football federations which resulted in the team's final renaming as Serbia national football team. During this period the team continued to officially carry old nickname Plavi badge and kit design indicative of Yugoslav tricolour.
The two sides started the football rivalry in 1990 when they were part of Yugoslavia which dissolved after a series of wars. The nations have played four times with Croatia winning one and drawing three games.