birthday confusion

...at the market today I picked up a snazzy little booklet full of Melbourne's "175th Birthday" events....and I got very confused...according to the booklet, the city dates from August 30, 1835.

but John Batman landed in May of that year, and signed his famous "treaty" on June 6 ...not that one would wish to contradict the lovely City of Melbourne, but I'd bet you the Yellow Peril to a brick that most Melburnians would say the city began with Batman and his "place for a village".

(having looked at my references, I'm told there is "some doubt" whether Batman made it to the site of the city as it is now...but it still seems odd to be crediting a group that arrived later with being the "first").