Fukuoka Prefecture Kasuga has a humid subtropical climate (Köppen Cfa) characterized by warm summers and cool winters with light to no snowfall.

After the Meiji restoration, the village of Kasuga was established with the creation of the modern municipalities system on April 1, 1889.

Kasuga has a mayor-council form of government with a directly elected mayor and a unicameral city council of 20 members.

In terms of national politics, the city is part of the Fukuoka 5th district of the lower house of the Diet of Japan.

Kasuga is a regional commercial center, and is largely a commuter town for neighboring Fukuoka.