From Middle English shameles, shamelees, schameles, schomeles, schomeleas, from Old English sċamlēas, sċeamlēas, from Proto-Germanic *skamalausaz, equivalent to shame + -less.

shameless

1. Having no shame, no guilt nor remorse over something considered wrong; immodest, brazen; unable to feel disgrace.
2. (obsolete) Not subject to other people’s shaming or reproach.
   • c. 1503–1512, John Skelton, Ware the Hauke; republished in John Scattergood, editor, John Skelton: The Complete English Poems, 1983, →OCLC ↗, page 62, lines 38–41:

     He shall be as now nameles,
     But he shall not be blameles,
     Nor he shall not be shameles;
     For sure he wrought amys, […]

• French: effronté, éhonté, sans scrupules, sans vergogne
• German: schamlos, unverschämt
• Italian: sfacciato, spudorato, svergognato
• Portuguese: desavergonhado, sem-vergonha
• Russian: бессты́дный
• Spanish: desvergonzado, caradura, descarado, impúdico