How did the old submarine determine the underwater position?

Mainly by inertial navigation, and now it is the same. However, there is a high-performance laser gyro inertial navigation instrument with high accuracy. In the past, we mainly relied on manual calculation, so that we can get our position underwater without any external factors and sensors. In order to reduce the error, when the submarine has the opportunity to use the submarine mirror or sail on the water surface, the sailor will correct the calculation according to the external reference, such as the position of the star, the sun or the island.