Where does “Heortfordscir” come from?

Heortfordscir (Old English) comes from Old English Heorotford, from Old English heorot, from Old English ford, from Proto-West Germanic furdu, from Proto-Germanic furduz, from Proto-Indo-European pértus, from Proto-Indo-European per-, from Proto-Indo-European pr̥tós — passed , crossed.

Ancestry of “Heortfordscir”, step by step

Heortfordscir traces back through two separate lines of ancestry.

via Old English Heorotford

StepLanguageWordMeaning
1Old EnglishHeorotfordHertford
2Old Englishheorotdeer, stag
3Old Englishfordford
4Proto-West Germanicfurduford
5Proto-Germanicfurduzford
6Proto-Indo-Europeanpértuscrossing
7Proto-Indo-Europeanper-before, in front; first; to go through
8Proto-Indo-Europeanpr̥tóspassed , crossed

via Old English sċīr

StepLanguageWordMeaning
1Old Englishsċīrbright; shire; county
2Old Englishburnastream
3Proto-West Germanicbrunnōwell, spring
4Proto-Germanicbrunnôsource; wellspring; fountain; brook; stream;...
5Proto-Indo-Europeanbʰréh₁wr̥well, spring, source
6Proto-Indo-Europeanbʰrewh₁-to boil; to brew
7Proto-Indo-Europeanbʰer-to bear, carry
Every word from Proto-Indo-European pr̥tósEvery word from Proto-Indo-European per-Every word from Proto-Indo-European pértus