The predecessor of Komárom Esztergom County,Komárom county andEsztergom county were founded byStephen I of Hungary. Both counties had parts that now belong toSlovakia. Throughout their history the borders of the two counties were frequently modified, and they were merged several times as well. When the castle ofEsztergom was captured by theOttomans in 1543, the leadership of the county fled from there. The castles ofÉrsekújvár,Komárom, andTata were the three border castles stopping theOttoman conquest for long decades. During theOttoman occupation of Hungary, Esztergom became the center of asanjak spanning across several counties.Komárom county on the other hand was continuously functioning, itscastle was never captured by the conquering armies. The general assembly of nobles in Esztergom county was reintroduced after the liberation of the city from the Ottomans, by armies led byJohn III Sobieski in 1696. The assembly was dissolved in both counties duringRákóczi's War of Independence, and then it was reformed after the war, in Esztergom county in 1710 and in Komárom county in 1712.
Esztergom county was one of the twocounties in which the leadership consisted of common nobles and not religious and political leaders (the other one beingPest-Pilis-Solt-Kiskun county). They were not granted the rank oflord-lieutenant unlike the leaders of other counties; they could only acquirevice-ispán and other lower ranks. The twocounties were first merged in 1786 byJoseph II, with the new center being Tata. The merged county was separated after his death in 1790, and both Esztergom and Komárom were granted the rank of county center. The noble leadership was replaced by county commissions in both counties in May 1848. The county commission of Komárom county functioned until the end of thewar of independence of 1848-1849, but the commission of Esztergom county was disrupted by the occupation ofimperial troops on 15 January 1849. After the war the leadership of the counties was headed byImperial–royal commissioners. In 1851 the parts of the counties that lay on the southern bank of theDanube were reorganized as Esztergom county with Esztergom as its center, and the parts on the northern bank were reorganized as Komárom county with Komárom as its center. These reformed counties only existed until 1860. After that the county commissions elected in 1848 restored them to their previous state. Towards the end of the 19th century, two towns in Komárom county —Lábatlan and Piszke — were added to Esztergom county, during the reorganization of counties in 1876.
After theTreaty of Trianon the northern parts of the two counties became parts ofCzechoslovakia. After thetreaty 44 villages from the formerKomárom county and 22 towns from the formerEsztergom county stayed inHungary. In 1923 the two counties were merged under the name "Administratively pre-merged county of Komárom and Esztergom". After theFirst Vienna Award in 1938, the two counties were restored to their former size. The size ofKomárom county also increased significantly because the area ofCsallóköz, which previously belonged toPozsony county, was also added to it, so it consisted of sixdistricts now, as opposed to the previous four.
As a consequence of the temporary armistice followingWorld War II the 1937 borders of thecountry were restored. Due to this a temporary administrative reorganization was conducted, where the previousKomárom andEsztergom counties were now merged for a last time under the name Komárom-Esztergom county.
The Komárom-Esztergom County Council, elected at the 2024 local government elections,[6] is made up of 15 counselors, with the following party composition:[7]