TAIPEI, Taiwan — The Republic of China on Taiwan inaugurated Lai Ching-te as its new president Monday, installing a relative moderate who will continue the self-governing island democracy’s policy of de facto independence while seeking to bolster its defenses against Communist China.

Beijing claims Taiwan as its own territory and has been upping its threats to annex it by force if necessary.

Mr. Lai accepted congratulations from fellow politicians and delegations from the 12 nations that maintain official diplomatic relations with Taiwan, as well as politicians from America, Japan, and various European states.

Mr. Lai entered politics as mayor of the southern city of Tainan and then rose to vice president.

He takes over from Tsai Ing-wen, who led Taiwan through eight years of economic and social development despite the Covid pandemic and China’s escalating military threats.

Mr. Lai, who served as vice president during Tsai’s second term, came across as more of a firebrand earlier in his career. In 2017, he described himself as a “pragmatic worker for Taiwan’s independence,” drawing Beijing’s rebuke.

He has since softened his stance and now supports maintaining the status quo across the Taiwan Strait and the possibility of talks with Beijing.

Mr. Lai will build on Ms. Tsai’s efforts to strengthen ties with America, which doesn’t formally recognize Taiwan as a country but is bound by its own laws to provide the island with the means to defend itself.