After World War II, the communist regime in Romania had a negative impact on the club's identity, forcing it to change its name and colours several times.

The constituent assembly was held on 25 May 1910, in the EMKE Café (today Astoria Hotel), a place that also had an important contribution in the identity, bohemianism and cosmopolitanism of the football club.

The next month, a touring team from England came to town: Bishop Auckland, the Northern League champions that season, NAC won with an incredible 8–0.

Before World War I, the club activated only on local and a regional level, they joined the eastern division of the Southern Hungarian League and in 1913 NAC won 25 out of 31 matches.

One of the most important games for the local community, in this period, was the match against Hungarian giant, Ferencváros, played in Nagyvárad, on 6 July 1913 and lost honorable by NAC, with the score of 2–4.

They beat Universitatea Cluj and Jahn Cernăuți, before it was defeated in the final by Chinezul Timișoara – who would win the first six Romanian titles after the Great Union.

In 1932–33, after another spell confined to the regional tournament, CAO appeared in an expanded national competition, organized as two parallel leagues of seven teams; they finished second in their division, while local rivals Crișana Oradea came third in the other one.

Two years later, with the national league reorganized into one division, CAO finished as runners-up, sandwiched between the two dominant clubs of the period, Ripensia Timișoara and Venus București.

So, they undertook a twelve-match tour in France and Switzerland, during which they beat (score 5–2) Olympique Lillois, who would become in that season the inaugural French national champions, and obtained a 3–3 draw against Marseille.

In the following year, the tour was in France and its North African colonies, and Oradea was spreading its fame with 21 victories and 4 draws, 110 goals scored and only 23 conceded.

Players who starred in CAO's green and white stripes in this period included: Ferenc Rónay, the first ever goalscorer for the Romania national football team (against Yugoslavia in 1922); Nicolae Kovács, a forward who was one of only five men to play at the first three World Cups; Iuliu Baratky, a Hungarian from Oradea who opted to stay in Romania throughout the World War II, becoming a legend at Rapid București and Iuliu Bodola, a prolific goalscorer throughout the 1930s and into the 1940s.

Club Atletic Oradea's team that participated in the 1932 and 1933 Tours of France, Switzerland and North Africa was formed of: Ștefan Czinczer – Andrei Glanzmann, Iosif Bartha, Vasile Chiroiu, Iuliu Bodola, József Moravetz, Coloman Braun-Bogdan, Elemér Kocsis, Nicolae Kovács, Ferenc Rónay, Takács, Kraus, Nicolae Roșculeț and János Remmer (player and coach).

The Second Vienna Award in August 1940 annexed northern Transylvania, including Oradea, to Hitler's ally Hungary, while Romania was in the throes of its own right-wing military dictatorship.

The players who helped the club to this historic achievement included some major Hungarian and Romanian footballers of the age: Gyula Lóránt was only 20 years old during NAC's title-winning season.

József Pecsovszky known in Romania as Iosif Petschovschi or simply ‘Peci’, was another young member of the successful NAC team and was capped by Hungary at the age of 21.

An attacking midfielder from Timișoara, of Hungarian extraction, Peci would later become a hero in Arad due to his starring role in UTA's three league titles in the 1940s, and then won two further championships with CCA București in the 1950s.

Nicolae Simatoc, a reserve, was the only ethnic Romanian in the NAC squad; he was kept out of the starting line-up by the all-Timișorean midfield of Petschovschi, Demetrovits and Juhász.

The championship starts to be played in the spring-autumn frequency, instead of autumn-spring, then all the teams were renamed after the new agreed model, for example, the clubs supported by the army end up wearing the abbreviations "CCA", "CA" or "ASA".

The situation of Oradea's football club seemed problematic, but Progresul was unexpectedly well organized, signing in the spring of 1955 a new manager, its former player (newly retired, at that time) Ladislau Zilahi.

The city of Oradea blazed brightly on the region's football firmament, with some of Hungary and Romania's greatest players of the age – one cup, and a league title in two countries – but it is now very much in the shadows: FC Bihor was dissolved on 12 January 2016 after a stormy history and in the spring of 2017 this dissolution subsequently realizing a strange reversed situation of the early 1960s.

In the same period the team was enrolled in Liga V.[13][14] At the end of the season CAO had an impressive ranking line, 24 wins, one draw and only one defeat, 146 goals scored and 21 conceded, 73 points, with 15 more than their main promotion rival, Dinamo Oradea.

CA Oradea won all his matches in the autumn campaign, scored 69 goals and conceded only 6, leading the league table with a total of 45 points.

The season was suspended during the winter break, due to COVID-19 pandemic outbreak, then on 21 May 2020, CAO was crowned as the champions of Liga IV, Bihor Series based on the results of the matches that were played in the autumn of 2019.

[16] The promotion play-offs were played on the Municipal Stadium in Zalău, and CAO was assigned in a group of three teams, together with CSM Satu Mare and Someșul Dej.

[19][20] CA Oradea had a good 2021–22 season and was ranked 2nd, out of 10, qualifying for Liga II promotion play-offs, where it was eliminated in the semi-final round, by Corvinul Hunedoara, 2–4 on aggregate.

[22] After 1945, the club was moved back in Romania, but this time under the communist regime installed by the Soviets, fact that led to the removal of any Hungarian names.

Some of them were lost in time, but for example, between 1951 and 1958, when the club was known under the name of Progresul Oradea used a triangular logo, with a bleu, blue and white water tower in the middle.

The new logo is composed of a white shield, with green vertical stripes, having a geometric shape inspired by the emblems used both in the interwar period and in the first part of the 1940s.

Starting with the 2019–20 season, CAO also adopted a red and blue kit, current colors of Oradea and Bihor County, city and region which it represents.

The "sleeping giant" was revived in 2017, after 54 years of existence, but despite the skepticism from the beginning, the fan-base was fastly organized, mostly due to socios program of the club.