Christianity has been intricately intertwined with the history and formation of Western society. Throughout its long history, the Church has been a major source of social services like schooling and medical care; an inspiration for art, culture and philosophy; and an influential player in politics and religion. In various ways it has sought to affect Western attitudes towards vice and virtue in diverse fields. Festivals like Easter and Christmas are marked as public holidays; the Gregorian Calendar has been adopted internationally as the civil calendar; and the calendar itself is measured from the date of Jesus's birth.