In Spain
In Spain, Book Day began to be celebrated since 1926 every October 7,[6] the date that Miguel de Cervantes was believed to have been born. But, it was considered more appropriate to celebrate this day in a more pleasant season for walking and browsing the books in the open-air. Spring was much better than fall. So in 1930 King Alfonso XIII approved the change of celebration of the Book Day on April 23, the supposed date of the death of Cervantes.
Source: https://en.wikipedia.org/wiki/World_Book_Day
It is highly important to promote reading in English in our English lessons.
Vicens -Vives has some proposals and lesson plans for some of its books.