Matt 24:7-8
7 For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places.
8 All these are the beginning of sorrows.
KJV
Rev 6:5-6
5 And when he had opened the third seal, I heard the third beast say, Come and see. And I beheld, and lo a black horse; and he that sat on him had a pair of balances in his hand.
6 And I heard a voice in the midst of the four beasts say, A measure of wheat for a penny, and three measures of barley for a penny; and see thou hurt not the oil and the wine.
KJV
The idea of a measure of wheat for a penny, and three measures of barley for a penny, is about the balances of commerce. Economics is going to be skewed, for that idea is about high cost just for a loaf of bread, i.e., hyper-inflation. That's the kind of state the world is in now, especially the once wealthy western nations.
Many businesses have been moving out of the West, and trade laws opened up (GATT, NAFTA, CAFTA), creating the ability to move manufacturing to poorer nations; this to try and drive the poorer economies up and bring western economies downward in order to balance the nations in prep for the coming one-world government (i.e., the kingdom beast of Rev.13:1-2). This has helped put many western nations in a state of hyper-inflation, their debt based currency systems being prepared to fall.
The U.S. debt-based dollar is a prime example, controlled by the private banking cartel called the Federal Reserve (a private banking institution run by international bankers with an appointed chairman; it is not a real part of the U.S. government at all. They control deflation and inflation of the U.S. dollar which creates depressions and recessions. Their system has moved the power of the dollar out of the people's hands and put it into their's.) The IMF (International Monetary Fund) and like internationalist banking cartels are used to filter our U.S. debt-based currency to poorer nations, without our vote, which is hyper-inflating our dollar making it worth less, and driving up prices of goods and labor.
The 4th Seal is also part of this movement aligned with what our Lord Jesus said in Matt.24:7-8:
Rev 6:7-8
7 And when he had opened the fourth seal, I heard the voice of the fourth beast say, Come and see.
8 And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.
KJV
Those 4 things that kill, the sword, hunger, death, and with beasts are metaphors for this world-wide working of the locusts for the end, stealing the wealth and power of God's people (see Book of Joel and 4 categories of the locust). It represents the four main categories of the beast's control over the earth through military ("sword"), commerce ("hunger"), religion ("death" - spiritual death through deception), and the political ("beasts").
The 5th Seal is about the events of Mark 13:9-13, the delivering up of some of Christ's elect to give a Testimony by The Holy Spirit against them. This can be seen as partially having already begun especially in foreign nations with Christians being beheaded for their Faith on Jesus Christ. It will continue, especially into the a portion of the 6th Seal when the false messiah arrives and is setup in Jerusalem.
The white horse rider of the 1st Seal is the coming false messiah, but he doesn't appear until the 6th Seal:
Rev 6:13
13 And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind.
KJV
That part of the 6th Seal is about the Rev.12:7-17 events when the war in Heaven between Michael and his angels vs. Satan and his angels casts Satan and his down to this earth. The idea of "untimely figs" is part of the parable of the fig tree, and is about the winter fig that grows in the winter but falls off in the spring. It's an early fig, and not the true summer fig. That is given as a metaphor for the coming false messiah and his idol worship event in metaphorical spring, prior to our Lord Jesus' coming at the metaphorical summer harvest.
These Seal events are the signs our Lord Jesus gave us in His Olivet Discourse of Matt.24, Mark 13, and Luke 21. They are all to occur in the final generation that will see Jesus' second coming. That's the generation that is to see 'all these things' like He said.