The car brand’s media agency, OMD UK, brokered the estimated £2 million deal.
ITV will air sponsorship bumpers at the start and end of commercial breaks. In addition, online ads and activation, including creative executions, will appear on the broadcaster’s online and catch-up platform, The ITV Hub.
Havas Worldwide and its digital and data shop, Havas Helia, created the work.
ITV will broadcast the Six Nations for the first time when the tournament begins this weekend, and the sponsorship covers all of the England, Ireland and Italy home matches in 2016 and 2017. The BBC has the rights to the other games.
Simon Daglish, ITV’s deputy managing director, commercial, said the partnership with the BBC was "a boon for rugby fans" because it kept the live games on free-to-air TV.
Sky was said to have bid aggressively for the rights last year but rugby chiefs wanted the coverage to reach as large an audience as possible.
Peugeot plans to use its sponsorship to promote the 308 GTi Sport model.