International Nurses Day
International Nursing Day (also called International Nurses Day) is an annual commemoration promoted by the International Council of Nursing that is celebrated around the world on May 12, the day of the birth of Florence Nightingale, considered mother of modern nursing.
The International Council of Nursing (ICN) has celebrated this day since 1965. In 1953 Dorothy Sutherland, an official from the US Department of Health, Education and Welfare, proposed to then President Dwight Eisenhower to proclaim a Nursing Day, but he did not approve. 
In January 1974, the decision was made to celebrate that day on May 12 as this was the anniversary of the birth of Florence Nightingale, considered the creator of modern nursing. Every year, the ICN prepares and distributes the International Nurses Day kit. The kit contains public information and educational material for use by nurses everywhere.
Petitions have been transmitted to UNISON to move this day to another date. It has been suggested to move it to May 21, the birth date of Elizabeth Fry, founder of the Nursing Sisters institution and known for her work with prisoners. 
Since 1998, May 8 was declared as Nursing Students' Day, with the intention of celebrating it annually. Although, as in 2003, Nursing Students' Day was celebrated on Wednesday, and within the week of May 12, Nursing Week (May 6–12) has been celebrated every year since then. ]
These are the themes of International Nurses Day since 1988:
Celebrations in the UK
Every year on May 12, the day is celebrated at Westminster Abbey in London. On this day, a symbolic lamp is carried from the Infirmary Chapel in the Abbey itself and carried by several infirmaries, until it reaches the abbot, who places it on the Altar. This gesture has the symbolism of the transfer of knowledge from one nurse to another. At St Margaret's Church in East Wellow in Hampshire, where Florence Nightingale used to attend, as she was born in Florence during her parents' stay, a church service is held on the Sunday following her birth day. 
In Spain, the nursing team is made up of the Graduated Nurse (University Degree) and the Nursing Care Technicians (Professional Training), both of whom celebrate this date on May 12.
Nursing Day is celebrated on May 15.
United States and Canada
National Nursing Week is celebrated each year between May 9 and 15. In the United States, it was regulated by President Richard Nixon in 1974.
On January 6 of each year, since 1931, Nursing Day (originally, "Mexican Nursing Day") has been celebrated. That year, the then director of the Hospital Juárez de México, José Castro Villagrana, instituted it, alluding to the fact that nurses are "a gift from the Magi" for hospital patients. Every year, the president awards recognitions of merit to outstanding nurses and nurses.
In Peru, the Peruvian Nursing Day is celebrated on August 30, coinciding with the festivities of Santa Rosa de Lima, patron saint of nursing in the country.
International Council of Nurses - International Nurses Day