I am uprooting Hydrangea, shall I keep it in my house in the winter?

Yes

The references i have looked at so far do not talk about hydrangeas that are uprooted overwinter, they talked about them being potted or how to keep them safe in the ground. This link offered the closest info to what you were asking about. Maybe contact your local nursery or agricultural extension. Best to you

https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-winter

If you are uprooting in the fall, then you probably should wait to re-plant until the spring when the conditions are better for plant to readjust to new area. Therefore, I'd keep it inside over the winter.

I'm in zone 4 and there are many established hydrangeas that have been around for years without being brought into the home. Maybe it depends on the variety? Here is information I found on google: "Since they bloom on previous years' growth AND the new season's growth, you can leave them all winter long to achieve double the blooms next spring. Do NOT prune the hydrangea back in fall. ... Mound the mulch or leaves around your plants at least 12” high to protect the flower buds that will bloom early next year." Hope that this helps :)

I did this and replanted it right away (in the Fall) and it did just fine!

You know those beautiful hydrangeas they sell on Mother's Day in the spring? A lot of people plant those, thinking they're the hardy hydrangeas but they are not. If it is that type of hydrangea, then, yes you will need to bring it in. Hardy hydrangeas are usually very hardy to extreme temperatures, so they don't need to be brought in. Hope that's helpful.