What is the country of origin of a submarine?

The country of origin of a submarine refers to the nation where the submarine was designed, constructed, and commissioned into service. Submarines can be built by various countries, each with its own naval shipbuilding capabilities and technologies. For example, the United States, Russia, China, and several European nations have well-established submarine programs. The specific country of origin can often be identified by the submarine's design, manufacturer, and service history.