MUARA, Indonesia — Indonesia, the world’s most populous Muslim-majority country, seems an unlikely place for a party dedicated to all things pig.

But last month on the shores of Sumatra’s Lake Toba, more than 1,000 people gathered for pig races, pig selfies and contests devoted to calling pigs and drawing pigs. They also came to eat a local delicacy, barbecued pork.

The festival was more than just a celebration of pigs. It was also a way for the area’s large Christian community to push back at government-sanctioned efforts to promote a conservative version of Islam throughout the country and in their home province.