The Middle Ages most certainly had rights and liberties, but they were given or withheld based on the kind of person you were: a slave had almost no rights, a serf only a few (serfs and slaves both existed in this period); a nobleman, especially a peer of the realm, had almost all the rights; and everyone in the middle had an unpredictable grab-bag of them.

A commoner couldn't sue a knight; a knight couldn't invest in a business; only Jews could loan money, but they couldn't use the proceeds to buy land. Two people could commit the same crime under the same circumstances and get completely different punishments, because one of them was a citizen of the city where the crime occurred and the other wasn't.

The Enlightenment's key innovation was to give everyone the same rights -- rejecting some rights (like immunity from lawsuit) as intrinsically unjust, and granting the rest to everyone.