Panapillai Amma

Ammachi Panapillai Amma was the title held by the morganatic consorts of the ruling Maharajah of Travancore as well as other title holding male members of the Travancore Royal Family.

Its literal translation is 'consort' since as per the formerly existent matriarchal system in Travancore, the Maharajah's sister was the Maharani, and not his wife. Thus the wife, a non-royal, took the title of Ammachi Panapillai Amma.

The Ammachis were mostly from families of the Thampi caste of the Nair nobility. The Maharajahs married these ladies through the Sambandham form of wedlock known as Pattum Parivattavum.

The Maharajahs of Travancore (current south Kerala) adopted the Matrilineal custom and inheritance prevalent in the land around the 14th Century AD. Accordingly, when a king died, his nephew (sister's son) would become the next ruler. So, in order to keep inheritance through Marumakkathayam and also to avoid power struggles, the Maharajahs and other title holding male members of the Travancore Royal Family opted for morganatic marriage with ladies mostly belonging to Nair caste and its sub castes. Even if they belonged to higher caste, like Kshatriyas (aristocrats), even then they were included in the Thampi sub caste.

Families from where Maharajas got married were known as Ammaveedus. It is believed that when the then Travancore King, Maharajah Sree Karthika Thirunal Dharamaraja shifted capital from Padmanabhapuram to Thiruvananthapuram, he brought along his four wives who belonged to the places namely Vadasseri, Nagercoil, Arumana, and Thiruvattar. The new houses, referred to as Ammaveedus (ancestral homes of Ammachis) were constructed in the new capital and were named Arumana Ammaveedu, Vadasseri Ammaveedu, Nagercoil Ammaveedu, Thiruvattar Ammaveedu. The Maharajah also passed a rule that all the Royal male members should only marry from one of the above-mentioned four Ammaveedus. This gave social prominence to the Ammachis as well as their homes.

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Wikipedia