However, the formal founding of the town by Spanish conquistadors was placed in the year 1851 with the union of the settlements in Apad and Calauag.

Calauag experienced a big controversy due to a decade-long boundary dispute with the neighboring town of Santa Elena in the province of Camarines Norte, which resulted in a Supreme Court case, Presidential intervention, and the loss of a quarter of its land area.

The Daang Maharlika or Pan-Philippine Highway runs at the town after Lopez in Southbound and after Santa Elena at the Northbound or from Manila.

At the north end of Quirino Highway, it meets Daang Maharlika in Barangay Tabugon.

The town center (poblacion) consists of 12 barangays and 11 blocks from the PNR Station in the east to Pinagkamaligan ES on the west.

Going west from Barangay Pinagtalleran via Quezon Street, there are five blocks of high concentration of shops, groceries, and banks.

It falls under the Type IV Tropical Climate which has rainfall is more or less evenly distributed throughout the year.

The former disputed nine barangays are under Camarines Norte's 1st congressional district, Represented by Josefina "Josie" B. Tallado.

In the Provincial Board, Calauag, together with the other municipalities of 4th District of Quezon is represented by three elected board members for the term of 2022 to 2025: Roderick "Derick" Magbuhos of Atimonan, Harold Butardo of Guinayangan and Isaias Ubana II of Lopez, and are members of ruling Nationalist People's Coalition (NPC).

Raymond Transportation, mostly bound for Bicol makes a short stopover at the town, being its headquarters and its historical route.

Santo Tomas Exit of STAR Tollway (E2) is preferable, as it does not require a detour to interior of Batangas.

The wireless network and internet are provided by national telecommunications companies PLDT (Smart), Globe and Dito.

Liquified petroleum gas meanwhile may be purchased per cylinder tanks in gasoline stations or in local distributors.

Petroleum products, such as gasoline, diesel fuel, and kerosene are imported to the municipality through local distributors of publicly-listed oil companies Pilipinas Shell, Petron, and privately-owned Chevron, operating under the name of Caltex, as well as independent player Uno Fuels with most stations located near the road junction of Rizal Street and locally known as Calauag rotunda and National Highway or AH1 Public Schools are operated by the Department of Education, through Division of Quezon and divided by two districts: The East District and The West District.