Thread for ideas where small inventions are introduced to some region at some point in time before they were in OTL.
Or actually adopted, when they were not adopted in OTL, despite being introduced.
To start:
- Stirrup in Western Roman Empire after Hunnic attack. The cliché one (in addition to the common Roman steam engine idea).
- Wheelbarrow invented in Mesoamerica, 1100.
- Yakhchal invented in pre-Columbian Southwestern US by Pueblo or Anasazi.