1990 AD., Germany, German Democratic Republic, 100th anniversary International Labour Day commemorative, Berlin mint, 10 Mark, KM 136.

Germany, German Democratic Republic (DDR or GDR), 100th anniversary International Labour Day commemorative, engraver: Harald Larisch, Berlin mint, 1990 AD.,
10 Mark (ø 31 mm / 11,91 g), copper-nickel-zinc, 12,00 g. theor. mint weight, mintage 747.000 , axes medal alignment ↑↑ (0°), plain edge with incuse inscription “10 MARK * 10 MARK * 10 MARK * 10 MARK * “,
Obv.: ARBEIT, BROT UND VÖLKERFRIEDEN / DEUTSCHE DEMOKRATISCHE REPUBLIK / 10 / 1990 · MARK / A / ·DAS IST UNSERE WELT· , hammer and compass emblem of the German Democratic Republic at lower center, Berlin mint mark (A) to r., value and date above.
Rev.: 1890 - 1. / Mai / 1990 , anniversary dates flanking International Labour Day date.
KM 136 .

Year / Mint Mark / Mintage
1990 A 747.000
1990 A 4,367 (proof issue)

International Workers' Day, also known as Labour Day in some countries, and often referred to as May Day, is a celebration of labourers and the working classes that is promoted by the international labour movement which occurs every year on May Day (1 May), an ancient European spring festival.
The date was chosen by a pan-national organization of socialist and communist political parties to commemorate the Haymarket affair, which occurred in Chicago on 4 May 1886. The 1904 Sixth Conference of the Second International, called on "all Social Democratic Party organisations and trade unions of all countries to demonstrate energetically on the First of May for the legal establishment of the 8-hour day, for the class demands of the proletariat, and for universal peace."
The first of May is a national public holiday in many countries worldwide, in most cases as "Labour Day", "International Workers' Day" or some similar name - although some countries celebrate a Labour Day on other dates significant to them, such as the United States, which celebrates Labour Day on the first Monday of September.

In 1889, a meeting in Paris was held by the first congress of the Second International, following a proposal by Raymond Lavigne that called for international demonstrations on the 1890 anniversary of the Chicago protests. For most countries, "Labour Day" is synonymous with, or linked with, International Workers' Day, which occurs on 1 May. Some countries vary the actual date of their celebrations so that the holiday occurs on a Monday close to 1 May.

More on https://en.wikipedia.org/wiki/International_Workers'_Day ; https://en.wikipedia.org/wiki/Labour_Day