Dedicated after Shiva, Kadasiddheswara Temple is the first temple you will be visiting as you enter the Pattadakal site. In size this temple is much smaller than say the Virupaksha Temple or the Mallikarjuna Temple , located further deep in the site.
Possibly this temple was constructed during the regime of the Chalukya king Vijayaditya (696 - 733 CE). And this temple remains as an example of one of the earliest experiments the Chalukya clans did in the temple architecture. Otherwise this is built in what is called the Nagara style of architecture.