from Tkinter import * def onclick(): pass root = Tk() text = Text(root) text.insert(INSERT, "Here, I start the text ...") text.insert(END, "... and here, I finish it.") text.pack() text.tag_add("here", "1.0", "1.4") text.tag_add("start", "1.8", "1.13") text.tag_config("here", background="yellow", foreground="blue") text.tag_config("start", background="black", foreground="green") root.mainloop()