Why did early printers use black-letter type for legal and religious works?

Early printers utilized black-letter type for legal and religious works primarily because it served as the direct model for the first movable type. When printing was invented in the mid-15th century, typographers sought to mechanically reproduce the formal manuscript styles that were already established and widely accepted for books and documents of that era.123

Because black-letter type was based on the formal, square-text Gothic handwriting prevalent in 13th- to 15th-century Europe, it was the natural choice for the period's most significant texts, including ecclesiastical writings and legal documents. While humanists later favored roman type for its perceived legibility and connection to classical antiquity, many printers continued to use black letter for non-humanist texts, maintaining its association with tradition, authority, and seriousness in religious and legal contexts.124