Then the LORD said, "My Spirit shall not strive with man forever, because he also is flesh; nevertheless his days shall be one hundred and twenty years." (Genesis 6:3)Just over 1500 years after creation, the world, with all its might, was pursuing the broad path to destruction. As death and bloodshed exploded upon the earth, man did not turn to God, but to himself. In doing so, man gave himself over to the vilest of passions, a vileness which the sons of God only increased.
Around the year 2469 BC, Noah was 480 years of age. Of Noah's ancestors, only Lamech (Noah's father) and Methuselah (Noah's grandfather) remained alive. Adam and Seth had long ago died. When Noah was born, the reality of natural death was just beginning to sink into humanity. Within the first 480 years of Noah's life, Enos, Cainan, Mahalaleel, and Jared had all died. The reality of natural death, by this point, had been set firmly in stone.
This was a new era of human history, and it was darker than it had ever been before. The storm clouds were already on the horizon; rain was on the way. God Himself had made it clear that man would have only 120 more years. After that, the flood would come. God would judge the earth and all people would be blotted out, except for Noah and the seven others who would board the ark. Noah was thus commanded to construct an ark— a construction project so massive that he might not have finished it until shortly before the flood.
The world was certainly in a sad state. Violence filled the earth. All people on the face of the earth were wicked, except for Noah. The righteous remnant at this point in history was indeed small. The Genesis account even leaves open to question whether Lamech and Methuselah were among the righteous. Neither of them are mentioned to have found favor with God (as is mentioned of Noah in Genesis 6:8).
Enoch, a preacher of righteousness, had been taken up by God prior to Noah's brith. In a sense, Noah replaced him. He was now the one who warned the world of the coming judgment. Noah, according to 2 Peter 2:5 was a preacher of righteousness. Hebrews 11:7 states that Noah in reverence prepared an ark for the salvation of his household, by which he condemned the world, and became an heir of the righteousness which is according to faith.
The world was marching to its coming doom. The storm clouds on the horizon did nothing to quench man's desire for perversion. Man refused to give glory to the Creator. At 480 years of age, Noah's sons, Shem, Ham, and Japheth, had not yet been born. Noah was seemingly alone in the world. At the most, he was married to a godly wife. And in such a twisted world, they must have found great comfort in one another as they waited for the coming flood.
State of the World (2349 BC): The Flood (Part 1) - Genesis 7:11
The Coming Flood of the Pre-Flood World - Genesis 6:17
State of the World (2948 BC): Noah's Birth - Genesis 5:28
God's Ark Which Noah Built - Genesis 6:14
Noah Found Favor In The Eyes Of The LORD - Genesis 6:8