Complex sentence: The Imperial Mariner Corps was definitively regularized and the Marine Corps was created (that took the place of the Naval Artillery) as also the Service of Assistance for Invalids and several schools for sailors and craftsmen.
Split into simpler sentences: The Imperial Mariner Corps was definitively regularized and the Marine Corps was created, taking the place of the Naval Artillery. The Service of Assistance for Invalids was also established, along with several schools for sailors and craftsmen.