You only need iron and carbon the rest is already alloyed steel. You can definitely make a good blade out of only iron and carbon, it won’t be stainless, it might be difficult to harden just right, but it will be flexible and hold a keen edge if forged right. The smiths of ole dealt with nastier steels containing all kinds of things making it worse, not better (such as excessive amounts of sulphur and phosphorus) so I’d say they’d manage.
You only need iron and carbon the rest is already alloyed steel. You can definitely make a good blade out of only iron and carbon, it won’t be stainless, it might be difficult to harden just right, but it will be flexible and hold a keen edge if forged right. The smiths of ole dealt with nastier steels containing all kinds of things making it worse, not better (such as excessive amounts of sulphur and phosphorus) so I’d say they’d manage.