Nawanagar was an Indian princely state in the historical Halar region, located on the southern shores of the Gulf of Kutch. It was ruled by the Jadeja Rajput dynasty and became a part of newly formed India. Its capital city was Nawanagar city, now known as Jamnagar. It had an area of 3,791 square miles (9,820 km2) and a population estimated at 336,779 in 1901. Its rulers, who use the title of "Jam Saheb" are of the same clan as the Rao of Kutch. They were entitled to a 13-gun salute. The state flag was a rectangular red flag with a white elephant, near and facing the hoist. During the British, the state was part of the Kathiawar Agency, within the Gujarat Division of Bombay Presidency.

Jadeja is a Rajput clan that inhabits the Indian state of Gujarat and the Tharparkar district of Sindh, Pakistan. They originated from Sammas of Sindh, a pastoral group, and laid a claim on the Rajput identity after marriages with Sodha Rajput women by adopting a process called Rajputisation.