Nogometni Klub Istra 1961, typically known as Istra 1961, was founded in 1961 as a result of a merger between two previously existing clubs, NK Uljanik and NK Pula. As a result, despite the team name referencing its birth date, the year of foundation is sometimes considered to be 1948, the year NK Uljanik was established.
Historically, Istra 1961 have played most of their football in the country's lower divisions. Between 1998 and 2001, they were competing in the Treća HNL, the third tier of the Croatian football league system, before gaining promotion to the second division. At the conclusion of the 2003–04 season, Istra 1961 finished in first place, were crowned second division champions and gained entry to the top flight, the Prva HNL.
To date, major honours have been beyond the club's capabilities and so many see their promotion to the Prva HNL as their biggest achievement. However, the closest the club have been to achieving major success was in the 2002-03 season, while the team were still playing in the second tier. That year, Istra 1961 reached the final of the Croatian Cup for the first time in history. Unfortunately, they ultimately lost 4-1 on aggregate to Hajduk Split. In 2006-07, they were relegated once again, but returned at the second attempt, in 2008–09, as league champions.
Despite the club's relative lack of success, several Croatian internationals have represented the team, with examples including Nikola Kalinić and Igor Pamić. Amongst the side's most notable foreign imports are Serbian international Marjan Marković, Bosnian international Asim Šehić and Malian international Kalilou Traoré.
Istra 1961 play their home matches at the Stadion Aldo Drosina, which is shared with local city rivals NK Istra Pula. The venue underwent significant renovations between 2009 and 2011 and is currently able to hold a maximum of 9,200 supporters.