British Flags

The English flag used on large depictions like the back of crew only came about in 1801. And its not English. It the Flag of The United Kingdom, a Union of England, Scotland and Ireland.

Remove the St. Patrick's cross, for Ireland and it goes back to 1606. Its still not an English Flag but that of Great Britain (A united England and Scotland).

Now I usually associate the Spanish Main with the 15 and 1600's so The Union Flag of 1606 could be OK. But this presents a problem with the flag provided for the ships which in its provided form only came about in 1707.

Lets says we will use the 1606 Union Flag. Then we also need to use an earlier ensign. By 1653 the red white and blue ensigns were used:

Between 1625 and 1653 just the red was used. 1653 to 1800 the Union with out the Cross of St. Andrew.

After 1800 the Cross of St. Andrew is added. Which on e do we use however? Well it depends on who the Admiral of the West Indies was since the colors are tied to rank. The Admiral at Jamaica in 1805 was a Rear Admiral of the Red (Navy List 1805).

So maybe based on the flags provided the time period is after 1801, before 1864 and when an Admiral of the White is in change of the West Indies?

And for those ships not in the Navy but running as British Privateers from 1694 to 1856:

Spain

The flag on the back of crew is a completely modern flag from 1981.

It looks like the same flag is used on the ships but it could be confused with an earlier more appropriate flag from 1785 which was used until 1931.
Based on the use of modern Spain's flag, and Since now Britian only used the white ensign on nval vessels I can say WK did no research and just chose modern usage for the flags. Pathetic.