The little horn arises from Rome's collapse
Daniel 7 describes four beasts representing four world empires. The fourth beast — Rome — has ten horns (the ten kingdoms that emerged from Rome's collapse in the 4th–5th centuries AD). The little horn arises among them, after them, uprooting three. This means the little horn is not a future figure — it arose out of the political fragmentation of the Roman Empire. That is history.
Its identifying marks
Daniel 7:25 gives four precise characteristics: it speaks great words against God; it wears out the saints; it thinks to change times and laws; and it rules for 'a time, times and half a time' (1260 day-years). Each of these is a historical, institutional description — not a biography of a future individual. The entity that rose from Rome's ruins, claimed to speak for God, persecuted dissenters, changed the Sabbath and church calendar, and ruled for approximately 1260 years (538–1798 AD) is identifiable from history.
2 Thessalonians and the temple of God
2 Thessalonians 2:3–4 describes the 'man of sin' sitting in the 'temple of God, showing himself that he is God.' Paul's audience had no rebuilt temple — the temple of God in the New Testament is the church (1 Cor 3:16–17, 2 Cor 6:16). The man of sin sits within the church, claiming divine authority. This is not a future political dictator. It is a religious institution claiming to stand in the place of God.
Key Verse
“He shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be given into his hand until a time and times and the dividing of time.”
Daniel 7:25