The May 1, 1955 date was especially significant in Austrian history because it was the tenth anniversary of the reinstatement of the 1929 Austrian Constitution, the one that had been discarded by Chancellor Dollfuss on May 1, 1934, following the civil war that destroyed the Social Democratic Party and created a one-party Austro-fascist state.
Also, May 1, 1955 had to be a time of optimism for Vienna and Austria because it was just two weeks before the signing of the Austrian State Treaty whereby the U.S., Great Britain, France, and the Soviet Union returned sovereignty to the Austrian state and ended their occupation of the country.
Most of the pictures of the parade was taken at around 10:15 in the morning at or near Schottentor (see the clock in the picture below). The first shows a float that is a globe with the words "World Holiday of Labor, 1 May." The float is built on a platform of two bicycles, and you can see the legs of the two people inside the globe moving it forward. At the rear right of the float is a man holding a flag, but I cannot tell what it represents. To the rear left is a banner whose words are mostly blocked by the float. It appears that a pretty good crowd is observing the parade.
|Float at Vienna May Day Parade on May 1, 1955|
|Another View of the Vienna May Day Float, near Schottentor|
|Marching Band in 1955 May Day Parade in Vienna|
|Float Celebrating Ten Years of Rebuilding Austria's Second Republic, With a Protest Message|
You can see the first float, plus some large crowds, and the Burgtheater in the background.
|The 1955 May Day Parade Ending at the Vienna City Hall|
No doubt speeches followed the parade.