Were land-based dowries considered preferable to cash dowries? I’ve heard of both being used in the Middle Ages.

Good question!

I think it depended on the circumstances: a cash-poor but land-rich family would probably prefer the latter, so they could use the money to make their estate profitable or just restore their balance books; a cash-rich family would probably prefer the former, because cash is usually a one-time injection fo capital whereas land is an asset that pays dividends every year.

I imagine it also depended on a number of other factors: where was the land in question located, and would it be practical to manage that estate from one’s pre-existing holdings? Did the bride’s family have land to spare, or was it more important to keep the fiefdom together for the sake of the heir? Which family was more important? Which one wanted the marriage more?