The history of the Maremmano Abruzzese did start in the Abruzzo mountain, and with the Pastore Abruzzese.
Dogs from the Abruzzese region was brought down to the Tuscan lowland of Maremma and to Latium, where they developed into a lighter breed that the original dogs of the Abruzzese mountains.
Despite of independent researches that pointed out the difference between the Pastore Abruzzese and the Maremmano (including ENCI's own "Characters differentials between Maremmano type and Abruzzese type" in 1938), ENCI decided in 1951 that the two breeds should be bred as only one breed. In 1958 the "joined" breed were given its current name; Cane da Pastore Maremmano Abruzzese.
The Pastore Abruzzese still can be found in its pure form in the Abruzzi mountains, while the Maremmano in its true form is gone, and have been replaced by the Maremmano Abruzzese.

You still can find Maremmano Abruzzese dogs that are used to guarding sheeps, but mostly the breed is owned as a companion or as a show dog. However, the guarding instincts is still present, and the dogs will do their duties with serious dedication.