Giulia repeatedly threatens to send Pantisilea to Tierra Del Fuego if she does not continue to spy on Lucrezia. The time frame for series is 1493-1494. Magellan is credited as the first European to visit Tierra Del Fuego (and give the area its name) in 1500.
SPOILER:The recaps identify each episode as taking place during one month only, always following the month in the previous episode, but events in the episodes proper flow way faster than that. For example, the season 1 finale opens with Juan Borgia's death (June 1497) and ends with Perotto and Pantisilea's deaths (February 1498). The recap in the first episode of the second season, set 8 months after that, still claims to take place in 1493.