Holy Family

450 Keller Ave. Waukegan, IL 60085

Office Hours


Monday - Friday

​8:30 am - 5:45 pm

Most Blessed Trinity


Santisima Trinidad

Queen of Peace

910 14th St. North Chicago, IL 60064

Immaculate Conception

508 Grand Ave. Waukegan, IL 60085

Most Blessed Trinity (MBT) Parish is a Catholic Church in the Archdiocese of Chicago and is located in Waukegan. This parish was named Most Blessed Trinity Parish in 2009 when Holy Family, Immaculate Conception and Queen of Peace Parishes merged. MBT is the largest parish in the archdiocese with approximately 7,000 individuals attending weekend liturgies, 85% of whom are Hispanic.

Originally there were six parishes. Now there is one parish, Most Blessed Trinity Parish.

  • Immaculate Conception Parish (Grand Ave.) was founded in 1841 to serve the Irish Catholics.
  • St. Joseph Parish (Martin Luther King Dr.) was established in 1870 for the German Catholics.
  • St. Bartholomew Parish (8th & Lincoln) started in 1896 to serve the Lithuanian Catholics.
  • Holy Family Parish was founded in 1902 as a mission of Immaculate Conception to serve the military personnel.
  • Mother of God Parish (510 10th St.) was established in 1903 to serve Catholics from Croatia, Slovenia and Slovakia.
  • Holy Rosary Parish (14th St) was founded in 1904 to serve Polish Catholics.
  • In 1991 St. Joseph and St. Bartholomew Parishes merged and became known as St. Joseph and St. Bartholomew Parish and was renamed Holy Family Parish in 1996.  Also in 1991 Mother of God, Holy Rosary and Holy Family (for military personnel) Parishes merged and became known as Queen of Peace Parish.
  • In 2009 Holy Family, Immaculate Conception and Queen of Peace Parishes merged and became known as Most Blessed Trinity Parish.


The mission of Most Blessed Trinity Parish is: Serving the People of God with a preferential option for the poor.  To walk with Jesus is to walk with the poor.  Waukegan is in Lake County, the 11th wealthiest county in the state. Over the latter half of the 20th century, Waukegan became the center for Hispanic immigration in Lake County. The population of Waukegan is now 90,000 people.  

Administrative Office


Holy Family Site

450 Keller Ave. 

Waukegan, IL 60085

Phone: (847) 623-2655

Fax: (847) 623-9479