The Jementah Civil War broke out in 1879 in Jementah in northern Johor when Tengku Alam Shah, the heir of late Sultan Ali of the autonomous principality of Muar refused to surrender the principality to the central administration of Abu Bakar, the then Maharaja of Johor.

As a compromise, Sultan Ali was granted a fiefdom over Muar region, while Temenggong Ibrahim ruled the rest of Johor.

Ungku Jalil handed over the custodianship of the Kesang territory and the Governor William Robinson recognised the fiefdom of Muar as having returned to Maharaja Abu Bakar's central administration in Johor Bahru, which greatly upsets Tengku Alam and many of his followers.

Tengku Alam and his followers launched the first blow of the war by seizing Jementah town, just outside Segamat, on 25 October 1879.

The headman or governor of Jementah reported to the ruler of Johor, Maharaja Abu Bakar, who responded by sending a powerful force led by his cousin, Ungku Ahmad.