All galaxies are descended from big clumps of gas that formed during the Big Bang. These gas clouds eventually formed into galaxies. So yeah, our galaxy can be

All galaxies are descended from big clumps of gas that formed during the Big Bang. These gas clouds eventually formed into galaxies. So yeah, our galaxy can be traced back to the very beginning just like every other one. There are lots of stages of galactic evolution. Its probable that the modern galaxy was cobbled together from many smaller ones (satellites, etc) over the eons. So with all the mixing and matching that has gone on over time, we've picked up many stars from many different stages of galactic evolution. Its not unusual at all to find such an old star.