Inglis was a Scottish calligrapher born in London to French parents, who produced about 55 miniature manuscript books between 1586 and 1624 and whose work was much admired and collected in her lifetime. Esther Inglis was a daughter of Nicholas Langlois and his wife, Marie Presot, French Huguenots who migrated to London in about 1569 and to Scotland by 1574. Presot was an accomplished calligrapher who taught her daughter writing. In about 1596 Inglis married Bartholomew Kello, a clerk and sometime cleric. All but three of her books were signed with her maiden name (meaning 'English') in either its French (Langlois) or Scottish (Inglis) form, although in modern libraries her work is usually catalogued under the name Kello. She was an expert calligrapher, writing a variety of hands with equal skill in miniature form. Sometimes the letters were scarcely a millimetre high. She also decorated her books with paintings and drawings, and she often included self-portraits in them (based on a portrait from 1595, now in the Scottish National Portrait Gallery). Inglis dedicated her manuscripts to European royalty, including Queen Elizabeth I, as well as to other aristocrats. It is likely that she was paid for her work.