What is "olentzero"

Olentzero (, sometimes Olentzaro or Olantzaro) is a character in Basque Christmas tradition. According to Basque traditions Olentzero comes to town late at night on the 24th of December to drop off presents for children. In some places he arrives later, for example in Ochagavía – Otsagabia on the 27th and in Ermua on the 31st.