Jagiellonia Bialystok

Jagiellonia Białystok was founded by soldiers in the Reserve Battalion of the 42nd Infantry Regiment on May 30, 1920. The team's original name was shortened to KSBZ 42 PP. Their first game was against Kresowcy Białystok which they won 5–1. Later the team name was changed to WKS 42 PP, an abbreviation for Wojskowy Klub Sportowy, which means Army Sport Club. On November 2, 1930 WKS 42PP lost 1–2 against WKS 82 PP for the play-offs to advance to Division 1. January 27, 1932 was the first time Jagiellonia was introduced into the club's name when it was changed to Białystok Sports Club Jagiellonia. The term Jagiellonia refers to the Jagiellonian dynasty which ruled Poland for two centuries. Around the same time, the club's coat of arms was also introduced with its red and yellow colours. In 1938, due to financial problems, the club dissolved and ceased to exist until its reactivation in 1945. Unfortunately, in June the following year, with the new government in place there was no room for Jagiellonia, mostly because of the history with the Bolsheviks in 1920 and the 42nd Infantry Regiment. On January 26, 1957 the merging of Budowlani Białystok and Sparta Białystok reactivated Sports Club Jagiellonia Białystok with the original yellow-red-black crest restored.

The club's crest and colours first appeared in 1932. The original crest consisted of a black, stylized letter "J" and a yellow and cherry red colour shield, while the flag and the jerseys of the club were white and black. It was not until the mid-80s that fans began to use yellow-red as club colours, but official documents at the time still use the white and black colours. Currently, the team's official colours are yellow-red, but in reference to history the team's away colours are white and black.

In 1920–1923, most of the matches Jagiellonia played were either friendlies or small tournaments in Białystok. The club joined the regular league in 1924, starting in klasa B in the Vilnius OZPN district. The season was a success, winning the first season and gaining promotion to klasa A. Due to a pause in the league, there were no games in 1925. In 1926, the league started up again with the team being in klasa A. The team was doing well, finishing third in the following season. Later through the years the match officials were being paid off to make the Białystok team not do well and ultimately get demoted. In 1929, it was decided to change districts where Jagiellonia played to the newly formed Białystok OZPN. In 1930 42PP, the club's name at the time, was the most successful thus far. They appeared in the play-offs for the top division in the country. At the end of the play-offs Jagiellonia and another team, WKS 82 pp Brześć, were tied for points and had to play one more game at a neutral ground to see who was the winner to that season. Jagiellonia fell to WKS 82 pp Brześć 2–1. Jagiellonia did win the district championship that season but it was the last trophy they won before World War II.

A big moment for the club was on January 27, 1932 when the WKS 42 PP football team and the KS Związku Młodzieży Wiejskiej athletics club merged to create a new multi-sports club called Białostocki Klub Sportowy (Białystok Sports Club) Jagiellonia. It is not known who created the team's new crest but what is known is that it had to do with the history of the Jagiellonian dynasty, which ruled Poland between 1386 and 1572. Several more departments were founded, including volleyball, basketball, boxing. The most successful team sport section was the volleyball team, which qualified to the Polish Championships in 1933 and 1934, finishing 7th and 8th respectively.

In the mid-thirties Jagiellonia began to experience problems, the city was not able to maintain the club. In 1932, the military stationed in Białystok took an active role in trying to save the club, along with the municipal government in 1936 the club's name changed to Military Sports Club Jagiellonia. Unfortunately, this decision did not solve the problem completely. In 1938, the club joined the A-class 1937/38 season but had to withdraw shortly after due to financial reasons. All the matches were cancelled and all the players were forced to find new clubs. Most of the players joined Strzelec Białystok and played there for two seasons before World War II broke out in 1939 and closed the first chapter in the history of the club.

After the second world war Jagiellonia was revived mostly in part by Karol Kowalczyński, but the revival was short-lived as the club dissolved on 20 June 1946. In the place of the disbanded Jagiellonia came Motor Białystok, which became the champion of the Białystok region and advanced to the Polish championship in 1946. Next year Motor Białystok joined the struggle for the Polish championship and the right to get into I league. In 1949 Białystok had a new team called Budowlani Białystok and in 1951 Motor Białystok merged into Budowlani Białystok. In 1955 Budowlani Białystok changed its name to BKS Jagiellonia Białystok. On 26 January 1957, a merger of two clubs, Jagiellonia Białystok and Sparta, resulted in a club called Jagiellonia. For the second time in its history Jagiellonia had the host stadium of Stadium Zwierzyniecki.

In the early 70s the team played in Klasa A and in the district league. The team's situation changed when Michał Urban became coach of the team, players started to go to a modern training camp with modern drills. Many young players started playing for the club, including future representatives for the Polish national team juniors. Grzegorz Bielatowicz joined the club as a scout and found a few young talents from the north-east region, among them was Jerzy Zawiślan who was the 2nd top scorer in the II League 1975–76 season who scored 13 goals. The team started to have some success and were promoted to Division II after winning the promotion play-offs in the 1974–75 season. The team was eventually promoted to League II in 1975, but the success was short-lived after only being there for 3 seasons, Jagiellonia was relegated in 1978. At the end of the 70s Jerzy Bołtuć, Leszek Frelek, Ryszard Karalus and Zbigniew Skoczylas began a large youth project to bring in a strong and young new team.

In the 1982–83 season, the club, led by Grzegorz Bielatowicz, had a successful run finishing first place with a nine-point advantage over second place, Gwardia Szczytno, promoting the team to Division II. With Olympic silver medalist Janusz Wójcik as coach, the team played a number of good seasons in Division II finishing third in 1986 and the following year was promoted to I Liga for the first time in the club's history. In addition, the top scorer in the competition was a later representative of Poland, Jacek Bayer who netted 20 times for Jagiellonia.

Matches in the second league in Białystok were already averaging 15 thousand viewers. The first match in the return to Ekstraklasa had estimated 35-40 thousand supporters. Every home match following the first was viewed by no less than 20 thousand fans in the stands. Stories from witnesses said they recall buses of supporters come from villages all over the region. The first few seasons did not turn out well for the Białystok team as they finished 8th twice and then 16th, which meant they were relegated. A year later the team lost the playoffs for promotion in a penalty shoot-out against Zagłębie Sosnowiec. In the following year Jagiellonia finished 2nd place earning them promotion to the Ekstraklasa. After only one season in the first league the team was significantly outclassed and were relegated, where they continued to fall to the 4th league. They did not spend much time in the bottom tiers; within 3 years Jagiellonia was back in the second league.

In 2007, the team advanced to the first tier, where they still are today. The first season back the team finished 14th place with 27 points. The following year was better where the club finished 8th with 34 points. In 2009, the club was punished with a deduction of 10 points following a corruption scandal, committed by the previous president of the club. The first success of the club was the 2009–10 season where Jagiellonia won the Polish Cup, beating Pogoń Szczecin thanks to a goal from Andrius Skerla. The 2014–15 season was the second most successful season Jagiellonia saw finishing 3rd place. In the 2016–17 season Jagiellonia were runners up for the first time in the club's history. Jagiellonia won the Polish Cup and finished 3rd and 2nd when coached by Michał Probierz.

Ireneusz Mamrot became the club's new coach in June 2017. With Mamrots' guidance the club won the silver medal as runners up in a very tight race for the Polish championship, thus earning them a spot in the Europa League for the 2nd time in a row.

In the 2018–19 season, Jagiellonia Białystok drew an average home league attendance of 9,458. In January 2019, Rafał Grzyb, having the most caps for the club and long time captain became the club's new assistant coach, officially retiring from playing football. On 23 August 2019, Jesús Imaz scored the first hat-trick in the club's history in the Ekstraklasa.

On 25 May 2024, Jagiellonia won the Ekstraklasa title for the first time in the club's 104-year history, following a 3–0 win over Warta Poznań on the final day of the season.

In the 2024–25 European campaign, Jagiellonia Białystok started in the UEFA Champions League second qualifying round, defeating Panevėžys with an aggregate score of 7–1 (3–1 at home, 4–0 away). In the third qualifying round, they faced Bodø/Glimt and were eliminated with a 1–5 aggregate loss (0–1 at home, 1–4 away). This led Jagiellonia to the UEFA Europa League play-off round, where they played against Ajax but were defeated 1–7 on aggregate (1–4 at home, 0–3 away). Jagiellonia then entered the UEFA Conference League league phase, where they started with a 2–1 victory over Copenhagen.