The Akritai declined in importance by the late 10th century , as the Byzantine conquests pushed the border eastwards .
Its defense radically restructured , with smaller themata grouped in five large regional commands headed by a doux and a heavy presence of professional troops ( tagmata ) .
The Akritai declined in importance by the late 10th century , as the Byzantine conquests pushed the border eastwards , and its defense radically restructured , with smaller themata grouped in five large regional commands headed by a doux and a heavy presence of professional troops ( tagmata ) .