Answer: Hawaii
There is perhaps no part of the United States which celebrates May Day as colorfully as Hawaii, since 1 May also serves as Lei Day when the culture of all of the different Hawaiian islands are recognized.

Answer: 1889
In 1889, during the Second International, a conference organized by prominent socialists, 1 May was declared as International Workers Day.

Answer: Saint Walpurgis
Large parts of Central and Northern Europe celebrated Walpurgis Night in acknowledgement of the saint of the same name who was canonized on 1 May, 870.

Answer: France
Under French law, work stops, yet workers are still paid, on May Day.

Answer: May 1
May Day, in its various incarnations, is usually held around the world on May 1st.

Answer: 17th Century
For a few years in the mid 17th Century, the church abolished May Day due to its revelrous nature until it was reinstated by King Charles II.

Answer: Kenya
Kenya is known for raising its minimum wage annually on May Day (which they refer to as Labor Day), sometimes to the chagrin of employers.

Answer: Spring Equinox / Summer Solstice
The astronomical foundation of May Day lies in it falling almost midway between the vernal equinox (usually 20 March) and the summer solstice (usually 21 June) in the Northern Hemisphere, the part of the world where May Day festivals are often relegated to.

Answer: United States
The bloody Haymarket Affair was a riot that took place in Chicago (United States) in 1886. This incident was founded in labor demonstrations.

Answer: Communist
Communists take May Day very seriously, which is why the holiday is so popular in places like Russia, China and North Korea.