When in 1518 the famous corsair Hayreddin Barbarossa became an admiral of the Ottoman Navy, he introduced several changes in the Ottoman naval flags, establishing definite guidelines and patterns that would long last. This way, long range merchant galleons were assigned a plain red flag, sometimes complemented by a green horizontal stripe to denote a «Haji» captain –that is, one having fulfilled the pilgrimage to Mecca.
Source: Jaroslav Martykán, «A history of Ottoman naval flags», XVII International Congress of Vexillology 1999
Sizes: ensign W12 x L18 mm, mast flags W8 x L12 mm, jack W6 x L9 mm, pennant W4 x L48 mm.