Thanks to Colin for many of these images.
See also http://www.austbuttonhistory.com/uniform-buttons-2/companies-and-clubs-including-merchantile-marine/?preview_id=4881&preview_nonce=acff4915a8&_thumbnail_id=-1&preview=true#BANKS
National Australia Bank
The NAB was formed from the merger of the National Bank of Australasia and Commercial Banking Company of Sydney in 1982.
St George Bank
St George’s was originally a Building Society formed in 1937. It became a bank in 1992. There have been mergers and acquisitions, notably of BankSA. In 2008 St George and BankSA became subsidiaries of Westpac. In Victoria, St George branches were rebranded as a (relaunched) Bank of Melbourne.
Originally the Bank of New South Wales (from 1817), the bank was rebranded in 1982.
Australia New Zealand Banking Group
ANZ was formed in 1951 from the merger of the Bank of Australasia (founded 1835) and the Union Bank of Australia Limited (founded 1837).
The official ANZ coat of arms has the motto ‘Tenax Propositi’ or ‘Tenacious of Purpose’ in the banner. It was granted in 1960. The official supporters are an Antelope and Unicorn, but the kangaroo and kiwi are nice.