Union Jack. Who's Jack?

Today's piece of knowledge actually seemed very obvious the second it was explained to me, however until a recent lecture I had never even considered the origin of our flag. I am certainly not a historian, so I simply accepted that it represented all sections of the British Isles. Let's see if you have the same eyebrow-raising moment of realisation, after this short history lesson.

In 1603, after the death of Queen Elizabeth, King James VI of Scotland came down to England, becoming King James I. There was hope that through this move, the two nations would become united, both with currency and flag.

Following the 'union of the crowns', in 1606 after proclamation by Orders in Council, the Union Flag was formed by merging the Saltire with St. George's Cross. King James' rule is termed the Jacobean period, hence the Union Flag is coined the Union Jack...! (Told you it seems obvious).

Union Flag, (English Version) with St. George' Cross and St. Andrew's Cross (Saltire).

It wasn't until a century later in 1707 when the two countries actually became Kingdom of Great Britain, up until this point they were still separate Kingdoms, with the Scotts having a slightly different version of the Union Jack (Union Flag), although not dominant.

Another century later in 1801, the Kingdom of Great Britain joined with the Kingdom of Ireland, and so it was not until this point that St. Patrick's Cross became a part of the flag that we are all so familiar with today.

Incorporation of St. Patrick's Cross following the joining of the Kingdom of Ireland
with the Kingdom of Great Britain.

During the months leading up the recent Scottish referendum for independence, one thing that struck me most is the chance that our unifying flag could be changed. To have a Union Jack without the very Saltire that contributed to it's original formation in the James' I, would have been a strange image.

Do you think the Union Jack still serves its purpose of unifying our nations? Please share your thoughts!