Thanks Sri Garg for the brief write up. Its history as per wikipedia is:
History
The history of Rameswaram is centred around the island being a transit point to reach Sri Lanka (Ceylon historically) and the presence of Ramanathaswamy Temple. Tevaram, the 7th–8th century Tamil compositions on Shiva by the three prominent Nayanars (Saivites) namely Appar, Sundarar and Thirugnanasambandar. The Chola king Rajendra Chola I (1012 – 1040 CE) had a control of the town for a short period. The Jaffna kingdom (1215–1624 CE) had close connections with the island and claimed the...
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title Setukavalan meaning custodians of the Rameswaram. Hinduism was their state religion and they made generous contribution to the temple. Setu was used in their coins as well as in inscriptions as marker of the dynasty.
According to Firishta, Malik Kafur, the head general of Alauddin Khilji, the ruler of Delhi Sultanate, reached Rameswaram during his political campaign in spite of stiff resistance from the Pandyan princes in the early 14th century. He erected a mosque by name Alia al-Din Khaldji in honour of victory of Islam. During the early 15th century, the present day Ramanathapuram, Kamuthi and Rameswaram were included in the Pandya dynasty. In 1520 CE, the town came under the rule of Vijayanagara Empire. The Sethupathis, the breakaway from Madurai Nayaks, ruled Ramanathapuram and contributed to the Ramanathaswamy temple. The most notable of them are the contributions of Muthu Kumara Ragunatha and Muthu Ramalinga Sethupathi, who transformed the temple to an architectural ensemble. The region was repeatedly captured several times by Chanda Sahib (1740 – 1754 CE), Arcot Nawab and Muhammed Yusuf Khan (1725 – 1764 CE) in the middle of 18th century. In 1795 CE, Rameswaram came under the direct control of the British East India Company and was annexed to the Madras Presidency. After 1947, the town became a part of Independent India.[15]