Open Secular Day is on the same day as UN World Book and Copyright Day.
"The Day – 23 April – is a symbolic date for world literature. It is on this date in 1616 that Cervantes, Shakespeare and Inca Garcilaso de la Vega all died. It is also the date of birth or death of other prominent authors, such as Maurice Druon, Vladimir Nabokov and Manuel Mejía Vallejo."
"Each year, UNESCO and the international organizations representing the three major sectors of the book industry – publishers, booksellers and libraries – select the World Book Capital for a one-year period, effective 23 April each year. This year the city of Incheon in Republic of Korea was chosen in recognition of its programme to promote reading among people and underprivileged sections of the population.
The Organization is also working with the International Publishers Association, the International Booksellers' Federation and the International Federation of Library Associations and Institutions to support careers in publishing, bookshops, libraries and schools."