The incident, which involved several people, took place at 4.17 am today (Friday, December 11) on Cambridge Road.
A man in his early 20s was taken to Leeds General Infirmary with head injuries while another man in his early 20s was treated for wounds to his back.
A 19-year-old man was also arrested on suspicion of actual bodily harm and criminal damage and remains in custody at this time.
Anyone with information is asked to call 101, select option 2 and ask for the Harrogate Investigation Hub.
Please quote reference number 12150219251.