Claim: On the feast day of Saint Nicholas, who is also known as Nicholas the Wonderworker, on December 6, children from Hungary wait for Mikulas, and receive presents while children in Czech Republic and Slovakia wait for Mikulas and his two assistants to deliver presents.
Evidence: Saint Nicholas of Myra (traditionally 15 March 270 – 6 December 343), also known as Nicholas of Bari, was an early Christian bishop of Greek descent from the maritime city of Myra in Asia Minor (Greek: Μύρα; modern-day Demre, Turkey) during the time of the Roman Empire. Because of the many miracles attributed to his intercession, he is also known as Nicholas the Wonderworker. 
Mikulás (or Szent Miklós) is the Hungarian version of Saint Nicholas, and a similar figure to Santa Claus. Still, it is believed that Mikulás arrives to celebrate his day, December 6 (while some countries celebrate it December 5), and leaves before Christmas. This tradition is also well known in Romania (Moș Nicolae), Slovenia (Miklavž), the Czech Republic, Slovakia (both Mikuláš), Croatia (Sv. Although the role of gift-giver on Christmas Day itself is assigned to the Christ Child, on the eve of Saint Nicholas' feast day of 6 December Hungarian children traditionally place a boot on their windowsill waiting for Mikulás to come by and fill it with treats. In the Czech Republic, Slovenia and Slovakia, Mikulás/Miklavž often comes with two assistants: a good Angel who gives out presents to good children and a "Krampusz", a mean elf, in some version a Devil, who punishes bad children.