The End The "end" spoken of is the Final days of the City of Jerusalem. The order of the Hebrew brings this out:
And the city and sanctuary, the people of a Prince, the coming One, shall destroy; and the end thereof shall be with that flood, and unto the End, war and desolatenesses decreed.
The article in front of Coming One denotes the fact that the Prince is not a present one, or a past one, but a future one. And he (He) is both a Prince and the Anointed One at the same time. (See vs.25, Acts 5:31 Him hath God exalted...to be a Prince and a Savior. Hebrews 12:2 Looking unto Jesus, the Prince and Finisher of faith. Acts 3:14-15 But ye denied the Holy One...and killed the Prince of life...)
Jesus was to be crucified ("cut off")in the middle of the last heptad that is, at the end of 31/2 years. But the consequence of that dastardly deed was to be a horrendous punishment: the Destruction of the city and sanctuary. That was the last straw in the wickedness of Israel, or as Jesus put it: fill up the measure (of sin) of your fathers (Matt. 23:32)
Jesus, the Anointed One, the Prince, also had said, The kingdom of God shall be taken from you... (Matt. 21:42) None of these who are bidden shall taste of my supper. (Luke 14:23-24) He shall come and destroy these husbandmen and shall give the vineyard to others... (Luke 20:13-19)
Daughters of Jerusalem, weep not for me, but weep for yourselves...For, behold, the days are coming in the which they shall say, 'Blessed are the barren'...Then shall they begin to say to the mountains, Fall on us...for if they do these things in a green tree, what shall be done in the dry? (Luke 23:28-31)
Flood The use of "flood" as a metaphor for an advancing army, was common in the Old Testament, and it accurately pictures the total devastation the Roman Legions left behind after a battle. A tsunami of destruction was to overtake the whole corrupt Judean country, not just the 'city and sanctuary'. (Compare Isaiah 8:6-8)
And notice the phrase, the people of the prince shall destroy in this verse. From what F. Josephus related about the Fall of Jerusalem (and other parts of Judea), the Zealot gangs caused much of the carnage and misery. So much so that the Roman General Titus, swore to God that he was not responsible for this disaster, but they did it to themselves! Competing gangs fought each other. And the Aristocracy fought the gangs. And Idumeans were hired to help the gangs fight rivals. Blood flowed freely in the streets. Gangs stole food from anyone who was cooking; and cannibalism prevailed.
Notice that verse 27 of Daniel 9 is a parallel of verse 26, but with added information. That is, it relates the same thing, but in a different way. (An expose of the amazing COVENANT would be off-topic here, but compare this covenant with many to the statements of Jesus at the Last Supper (And see Isaiah 53:11, Matt. 20:28, 26:28, Jer. 42:2)
A reading of the ancient Septuagint would be in order here:
And one week shall establish the covenant with many, and in the midst of the week my sacrifice and drink-offering shall be taken away; and upon the Temple shall be the abomination of desolation; and at the end of time (See Daniel 12, 1335 days) an end shall be put to the desolation.
Considerations Considering the fact that "flood" is a metaphor for army invasion, and that subsequent history has shown that, altho Jesus was crucified (and risen), the Destruction of Jerusalem and the Temple did occur...and that it occurred as a consequence of the Seventy Week prophecy in the first century...we can logically conclude that the main topic of coming to an END was the Jewish pride and joy: the Temple and capital of Judaism.