"In 1880, the age of consent was set at 10 or 12 in most states, with the exception of Delaware where it was 7."
The age of consent for heterosexual acts in England was set at 12 in 1275 during the reign of Edward I. The wording was along the lines of "It shall be deemed illegal to ravage a maiden who is not of age" - at the time "of age" being 12. Therefore, there was technically no age of consent for the male participant. The English law became applicable in Wales following the Laws in Wales Acts (1536 and 1543). In medieval Welsh law there was no actual equivalent of the concept of the age of consent as such, but a girl was marriageable at 12–14 (the onset of puberty) and a fine was payable for the taking of a girl's maidenhood by force; the rules varied according to status and may not have been applied rigidly to commoners.
A concern that young girls were being sold into brothels led Parliament to raise the age of consent to 13 in 1875 under the Offences against the Person Act 1875. After W. T. Stead's Maiden Tribute articles, the Criminal Law Amendment Act 1885 raised the age of consent to 16.