Sebastian, 28, has been capped three times for Scotland, having made his international debut against Japan in November 2021, with the prop’s father born and raised in the Scottish capital.

Sebastian is well known to Scottish rugby fans on the west coast, where the tighthead impressed while playing for Ayr RFC during a season-long partnership contract with Glasgow Warriors in 2015/16.

On returning north of the border, Sebastian said: “Leaving Scarlets certainly wasn’t an easy decision and I’ve got a huge debt of gratitude to the club. They are my home region and gave me my first opportunity to play professionally.

“However, this move to Edinburgh is massively exciting and it’s an opportunity that I genuinely can’t wait to get stuck into. The club is really ambitious with a talented squad and cracking new stadium, and Edinburgh is a beautiful city.

“This is a fresh challenge for me and one that really excites me because of my aspirations to continue playing international rugby. Hopefully I can keep myself in a strong position with Scotland by playing consistently for Edinburgh.

“I obviously know quite a lot of the Edinburgh boys from Scotland camp. I can’t wait to link up with the squad this summer and hit the ground running.”

The Carmarthen product was part of the Scarlets academy and represented Wales at both U16 and U18 levels.

Following a stint at Scotstoun, Sebastian returned to Scarlets at the start of the 2017/18 season, making his then-PRO14 debut against Cheetahs in February 2019.

The prop enjoyed a breakout campaign at Parc y Scarlets in 2020/21 – featuring 17 times for the West Wales side, 10 as a starter.

That form earned Sebastian a call-up to the Scotland squad for Summer Test fixtures against England A, Georgia and Romania, all of which were eventually cancelled due to Covid-19.

The tighthead eventually made his international debut that autumn – coming on as replacement against Japan at BT Murrayfield – before featuring in two of three Tests against the Pumas in last summer’s tour to Argentina.

Sebastian made his 65^th appearance for Scarlets from the bench in Saturday’s BKT United Rugby Championship clash against Edinburgh Rugby in Llanelli.

Head Coach Mike Blair, added: “Javan is a player that we’ve been able to track for some time and we’ve been hugely impressed with his performances for both Scarlets and Scotland.

“He’s an excellent scrummager which we want to develop into his super strength and he has the skill set to thrive in our environment.

“We know the Scotland coaches and staff are impressed with his work on the tighthead side and what he brings to the position. He’s also a great guy who will fit in well with our culture here at Edinburgh.

“We’re really excited to welcome Javan to the club this summer.”