Williams has signed from Mosely where he has been playing since leaving Wales in 2007. The 27-year-old has represented Wales at every age-group level and lists the Scarlets, Llanelli’s and Narbeth as his former clubs.
Brown joined the Blues in the summer of 2010 and made several starts for the region in their 2010/11 campaign.
The former Wales U21 international played for the Wales under 21 side in the Six Nations and was selected for the U21 World Cup in 2004 playing against South Africa, England, France and Russia.
“These are two important signings for us,” said Dragons Forwards Coach Danny Wilson. “I worked with Tom for 2 seasons at London Welsh and he is a great ball-carrier with a fantastic turn of pace.
“He was unfortunate on joining the Blues last season that a knee injury prevented him from cementing his place in the squad early in the season but he has put in some strong performance since his return to fitness. He has a great character and his work ethic will fit in with the boys really well.
“Nathan’s a strong scrummager. The Mosely pack has a reputation for its dominance and Nathan has been an important part of that. He will bring extra competition for places in the front row and of course he is a Welshman and it’s great to be bringing him home.”
