The first inhabitants of the place came from the Municipality of Sarat , Ilocos Norte people living in said part of the municipality are industrious and upon their arrival in this part of San Nicolas , Pangasinan, they decided to settle here and build their homes. Historical records disclosed that the first settlers were the families of Mr. Roque Perico, Mr. Felix  Perico , Mr. Juan Perico , Mrs. Antonia Lampa, Mr. Juan Goltiao , Mr. Eustaquio Equila and Sixta Lor.  Because of their love for the place , they made mutually agreed to name the barrios into barangays.

            A barangay election was then held pursuant to Presidential decree issued by then Pres. Ferdinand Marcos and the first barangay officials elected 1972 were. Eligio Lampa. Sr. Brgy . Capt. Juan Perico , Agripito Yranon , Felimon Garcia Cornelio Lucas,Anatalio Seriosa and Martin  Hora,Councilmen ,Amado Aguilar was also appointed as Barangay Secretary and Treasurer .

            Today , the composition  of Barangay officials are : Virgilio F. Soria barangay Captain : Dionisia C. Dotimas ,Romy B. Vicente ;Menandro G.Fontanilla Domingo  Layco , Juanito Abaya Roberto Hora, Jaime Seriosa as Barangay kagawad with Mike V. Layco as elected Sangguniang Kabataan Chairman Appointed members of the barangay Council of Brgy. Casaratan were : Perfecto O. Ibasco and Jovita R. Callanta as barangay Secretary and Treasurer respectively .

            The primary sources of income/ livelihood in barangay Casaratan are : farming , piggery livestock, gravel and sand: other sources of income includes teaching profession and employment in the government services.

            The inhabitants are members of the different religious congregations. Among the dominant religious congregations includes the Roman catholic , the Iglesia ni Cristo ; the United Methodist Church , the Seventh day Adventist and United Church of Christ  in the Philippines.

Summary:

Barangay          :  Casaratan

Population         : 963( 1995 census)

No. of Households : 192  ( 1995 census)

Distance from Municipal hall ; 1 kms.

Land. Area        : 40 has.

Facilities           : brgy.hall / Basketball Court ( cemented)

Road Condition : Cemented/ Gravelled

Public Utility vehicle : Tricycle/kuliglig

Sources of Potable Water : Deep Well

Source of Electric Power  : PANELCO III

Mineral Water    : Sand / Gravel/ Boulders
Tourist Attraction :

Farm product     : palay