Make military equipment in factories and complete operations in the Military Headquarters to get military influence points and earn new titles. To find out what title you are currently holding, open the Military Headquarters window and take a look at the top part of the window. Your title will be listed there. You can also view all titles you can earn when gaining more experience.
Press on the experience bar to the right of the title to see a list of titles, as well as information about how many points you need to gather to get them. New titles unlock access to new factories, bases and types of equipment. They also earn you new rewards.

Have fun playing the game!