It only takes a little knowledge of history to know that most real-world land claims actually go back to either conquest or to some kind of squatting on land that someone else had a nominal claim to. Few real-world land claims go back to the original peopling of the earth. So there are problems with both halves of section 35 of John Locke's 2d Treatise on Government: “Of Civil Government” (in Chapter V "Of Property"):

It is true, in land that is common in England, or any other country where there is plenty of people under government, who have money and commerce, no one can inclose or appropriate any part, without the consent of all his fellow-commoners; because this is left common by compact, i. e. by the law of the land, which is not to be violated. And though it be common, in respect of some men, it is not so to all mankind; but is the joint property of this country, or this parish. Besides the remainder, after such inclosure, would not be as good to the rest of the commoners, as the whole was when they could all make use of the whole; whereas in the beginning and first peopling of the great common of the world, it was quite otherwise. The law man was under, was rather for appropriating. God commanded, and his wants forced him to labour. That was his property which could not be taken from him wherever he had fixed it. And hence subduing or cultivating the earth, and having dominion, we see are joined together. The one gave title to the other. So that God, by commanding to subdue, gave authority so far to appropriate: and the condition of human life, which requires labour and materials to work on, necessarily introduces private possessions.

What force John Locke's argument here had in the era when he wrote it comes mostly from his clever use of the Bible. Here two of the Bible verses he is alluding to:

In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return. (Genesis 3:19)

And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth. (Genesis 1:28)

But even in John Locke's reading of Bible verses, there is a serious problem, akin to the problem I mentioned above. "Be fruitful, and multiply, and replenish the earth, and subdue it," which sounds the most like land claims based on the peaceful peopling of the earth, is a Bible verse from before the Fall. The verse requiring unpleasant labor is in the third chapter of Genesis, after the fall. The fourth chapter of Genesis moves toward the reality of where land-claims come from:

And Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him. (Genesis 4:8)

The rest of the first five books of the Bible, where God promises land to the Israelites that they ultimately claim in bloody conquest, completes a more realistic picture of where land claims come from. 

My focus here is on land claims in John Locke's before-the-Fall model and land claims in what believers would call our actual fallen world. But it is worth also pointing to the Bible's contrast between labor after the Fall, as described in the third chapter of Genesis and labor before the Fall, as described in the second chapter of Genesis:

And the Lord God took the man, and put him into the garden of Eden to dress it and to keep it. (Genesis 2:15)

Reducing human violence—which Steven Pinker talks about in The Better Angels of Our Nature—is much more important, but it would be a great advance in human happiness if we can figure out how to make the experience of work more like dressing and keeping the Garden of Eden than eking out survival from thorny ground by the sweat of our brows. 

Don't miss other John Locke posts. Links at "John Locke's State of Nature and State of War."