Goofs

When Barbarossa first interviews First Mate Renzo, Barbarossa is seen leaning against the deck rail. The camera angle changes and he is suddenly hunched forward, leaning on his knees. The camera angle then changes again to show him leaning against the deck rail.

When Barbarossa's ships broadside the Spanish galleons, the galleons return fire. There is much smoke on the decks of both ships. As Barbarossa's crew boards the galleon and the fight scene ensues, the smoke from the broadside is still visible, and then it is suddenly gone, and then back again, then gone and then back, etc.

When Barbarossa's crew returns shore after the battle with the Spanish galleons, Peg Leg is one of the first to come ashore. The camera angle changes to show all the boats coming on shore, and Peg Leg is nowhere to be seen.

On a few occasions, Pegleg's missing leg appears.

While the disguised Barbarossa is being followed with the ransom for the Alida, the scout for the trailing party returns and tells his captain they are "about two kilometers ahead".

The movie is set (according to the opening titles) in the 17th century. The metric system as it currently is did not appear until the late 18th century. There were attempts to use decimal measurements previously, but not based on the 'meter'.

At 4:20 into the movie, Barbarossa looks out to see a ship just sitting there. It's a calm sea, but water in front of the ship is churning up as if there were a propeller running. The sails are somewhat full, but a man on deck it complaining about dead winds.

The line "They're still alone, only about two kilometers ahead." betrays anachronism because the unit of distance kilometer wasn't put into use until a much later time in history.