A private religious building was opened by the High Sheriff of Bedfordshire, Colin Osborne on Thursday.
The library contains works on the Bahá’í faith and the history of Persia, plus books on major world religions.
The Bahá’í faith was founded in Iran by Bahá’u’lláh in 1863.
The library in Sandy, is to be used by students and academics to engage in historical studies.
The majority of the books and manuscripts were collected by the late Hasan Balyuzi, a historian, author and BBC radio announcer who was prominent member of the Bahá’í community until his death in 1980.
Trustee Dr Moojan Momen, a partner at Sandy Medical Centre and a resident of Northill, will oversee the library. Visits will be by appointment only.