All populations are inbred if you go back far enough. Consider, if all humans are not inbred, then you and I must have 4 distinct parents, 8 distinct grandparents, 16 distinct great-grandparents and so on. This leads to rather large numbers fairly quickly.
Assume an average breeding age of about 30 years (I realize that this is probably too high since life expectancies tend to about 30 years if you go back far enough, but it makes the math simple and lowering that age just lowers the time periods I am discussing). Then each succeding generation would represent the population needed to sustain us as completely non-inbred, and this number would double each time you go back 30 years. Thus, 30 years ago, there would have to have been 4 distinct people in the population to serve as our parents, 60 years ago, there would have had to be 8 distinct people to serve as our grandparents, etc.
Now, using those assumptions, at a time 960 years ago, there would have to have been roughly 8.6 billion people alive to serve as our distinct set of ancestors. That’s more people than are currently alive, and nobody has ever given population estimates that suggest that the world’s population has declined in the last millenium, so I would suggest that this renders it impossible that we aren’t inbred to some degree. (Going back even farther makes the point even more definitive; you hit 10 billion at 990 years, 100 billion at 1080 years, and 1 trillion at 1170 years.)