The Royal Bank of Scotland has a long history of acquisitions - originally having expanded its base into England and Wales
with the purchase of several banks decades ago.
In 1970, it folded its English banks into one subsidiary, calling it Williams and Glynn's. It had over 320 branches in England and Wales. (By comparison, the NatWest had 3,200 branches in England and Wales at this point in time). The Williams & Glyn’s name disappeared in 1985, when it was merged fully into The Royal Bank of Scotland.
They've also bought up some of the UK's middling-sized building societies.
In the USA, it's Citizens Financial Group subsidiary became a wholly-owned subsidiary in 1988. Since then, Citizens has acquired a number of other banks in Connecticut, Massachusetts, New Hampshire and Rhode Island, now making it one of the 40 largest banks in the USA.
In 2000, the RBS acquired the UK-based National Westminster Bank, turning the RBS Group into the third banking group in the UK.
It also created the Royal Bank of Scotland Group Insurance Co Ltd (mmmmm - catchy!) in 1984 which, now better known as Direct Line, sold its first motor policy in early 1985, and revolutionised the UK motor insurance market by selling direct to the public via the telephone, cutting out brokers.
Since Direct Line introduced its red telephone on wheels in 1990, it has built up the most-recognised advertising in the UK. The first sound trademarked in the UK was the annoying little bugle call it makes as it rolls into view. Direct Line seems intent on taking over the world, launching house and contents insurance in 1988, loans in 1993, mortgages in 1994, life insurance in 1995, savings accounts, a PEP unit trust and travel insurance in 1996, pet insurance in 1997, pensions and breakdown insurance in 1998, and, in 2000, jamjar.com an web site for buying cars on-line.
From its standing start, Direct Line is now (Q4 2002) the UK's largest direct motor insurer, third largest breakdown recovery provider and sixth largest home insurer. Before all the other insurance companies set up direct-to-the-public subsidiaries, they were insuring 40% of all cars in the UK.
The entrepreneur who persuaded the RBS to let him use their money to set up Direct Line was bought out outright by them, as the newspaper headlines comparing his personal pay and bonuses with the entire RBS Group's profits eventually became too embarrasing for them.
Notes on the article above: Strictly speaking, Scottish bank-notes are not legal tender in England and Wales, but as they are all represent one pound Sterling, it makes little practical difference - other than the vicious fights with snotty nosed litte Englanders running newsagent stands on London streets.
Additionally, UK coinage is not completely uniform - there are National variants of the one pound coin, but they are all issued by the Bank of England - which itself is actually the UK national bank, originally set up by an ex-pat Scot.