The chain was launched by Michael Marks and Tom Spencer as a 'Penny Bazaar' stall in Kirkgate Market in Leeds in 1884, with just £5 of goods.
In 1919, the pair opened their first Glasgow shop, right, at the corner of Virginia Street and Argyle Street.
With their policy of "nothing over 5 shillings" (25p), sales in the Glasgow branch were soon second only to those of London.
By 1925, Marks & Spencer had upgraded its Glasgow shop, on the same corner site, to "high street" status, dropping the "Penny Bazaar" display.
The M&S store in the street today, on the corner with Glassford Street, just along from this shop, opened in 1966, on the site of the former Mann Byars and Co household emporium.
It, in turn, had been built on the site of the city's old Black Bull Inn, a hotel often frequented by Robert Burns.
Next time you're passing, have a look at the plaque that marks this fact. It's on the Virginia Street corner of the M&S building.
Looking at this picture, we can't help but wonder what messages the girls in her long duster-coat was going in to buy. It certainly wasn't a sandwich or a new pair of bloomers!
Today, the firm has 703 UK shops and a further 361 stores spread across more than 40 countries.