The Commonwealth Games debutant, from Clapham Chasers in London, previously represented VP-Glasgow in track and field as a youngster and ran cross country for Edinburgh University Hare and Hounds.
Davis landed her Team GB debut at Tokyo 2020 after an impressive win in the trials in London a year ago.
And, only three years on from her first marathon, she then finished an impressive 39th out of a field of 80 last August in a stifling hot Sapporo in a time of 2:36.33.
Davis, remarkably, has never represented Scotland at any age group or discipline, with a Scottish Unis and College vest in cross country her only representative honour prior to the Olympics.
Now she becomes the seventh athlete announced as part of Team Scotland in track and field and marathon with six other Olympians pre-selected last October – Laura Muir, Eilish McColgan, Jemma Reekie, Josh Kerr, Jake Wightman and Andy Butchart.
“I am delighted to be selected for the Commonwealth Games but also for my first outing for Team Scotland and indeed Scotland in athletics in any way,” said Davis.
“My last major marathon was at the Olympic Games in Japan last year, which was an incredible experience.
“Because of Covid, we had to travel solo, so I am excited that my next major competition will be closer to home so my family and friends can watch roadside and soak it all in with me.
“Birmingham will be very different, hopefully, with family and friends able to come and watch and support.
“My mum and dad, Lynn and Mike, will look forward to that and, of course, there’s an opportunity for British-based athletes to go and do a recce of the marathon route. I am planning to do that.
“I have been training at home for the last couple of months and I’m really looking forward to building the volume and intensity over the next 14 weeks with my new coach Tim George.’
Davis has been part of the scottishathletics Marathon Project since the programme launched, with a view to raising Scottish standards and representation in the event.
Since then, three athletes were selected for the Olympics and another on the project, Luke Caldwell, is preparing to represent GB and NI at the European Championships in Munich in August.
Team Scotland chef de mission, Elinor Middlemiss, said: ‘I am delighted for Steph that she has been selected to represent Scotland at Birmingham 2022.
"Steph had a really good run in Tokyo under tough conditions and I am looking forward to seeing her compete on the road this summer.”
The women’s marathon will take place on Saturday, July 30 and will start in Smithfield – also the venue for the Birmingham 2022 beach volleyball, basketball 3×3 and wheelchair basketball 3×3 competitions.
Runners will first complete two 18k loops before heading south out of the city towards Bournville.
This is followed by a 6.2k section through the city centre, which finishes in Victoria Square, the location for the Town Hall and the Council House.