 Complete the following phrase:  From around 1450, three major naval powers established a domice over different parts of the Mediterranean using galleys as their primary weapons at sea: the Ottomans in the east, Venice in the center and Habsburg Spain in the west. The core of their fleets were concentrated in the three major, wholly dependable naval bases in the Mediterranean: Constantinople, Venice, and Barcelona. Naval warfare in the 16th century Mediterranean was fought mostly on a smaller scale, with raiding and minor actions dominating. Only three truly major fleet engagements were actually fought in the 16th century: the battles of Preveza in 1538, 