numerous attempts at union had been proposedduring the 1600s - scotland was especially keen on a 'federal' approach, where they would not be subordinate to Westminster, all these attempts had failed
william (III) of orange needed more money to fund his army; taxes were raised on trade (rather than land) and scotland at the time was a significant trading power but not subject to england taxes - the scots therefore seemed like a helpful and ready reservoir of money as well as manpower for the army
Acts of Union - Background 2
there was also continued concern over accession to the crown and potential scottish claims
in the end, the scots negotiated a union, bit it was long long before their negotiations seemed rather inept - minimal english investment and much higher taxes in scotland, and far fewer peers and MPs than even cornwall
Act of Union - Scottish Powers
scotland kept its own church, legal system and local government
scotland's coinage, tax, trade, parliament and flag became one with England
some of these powers have now been devolved back to scotland
Act of Union - 20th Century
by the 1970s there was political support for devolution to a scottish assembly a referendum was held in 1978m but the 'winning threshold' was not met
another referendum was held in 1997, this time resulting in a vote for devolution to a scottish parliament
Act of Settlement - Back to Independence
scotland held a referendum on independence in 2014, which narrowly resulted in a vote to remain part off the UK - this led to further powers being devolved to scotland ('devo-max')
this issue is back on the table as a result of the brexit referendum, when scotland voted remain compared to the UK overall leave vote