https://www.reddit.com/r/todayilearned/comments/sb7wgl/til_in_middle_english_the_letter_%C3%BE_called_thorn/
Jan 24, 2022 · TIL in middle English, the letter "þ," called "thorn," was used for "th." "The" was written as "þe". In English blackletter, the "þ" and "y" glyphs look similar.