As others have remarked elsewhere, Jesus clearly told many of his parables more than once, and so it should not be surprising to us when he adjusts the details of those parables in different settings to teach and challenge listeners in different ways. What can the context of this event tell us about Jesus' motivations at this moment?
The Parable of the Ten Minas is told in Zacchaeus' home, immediately before the Triumphal Entry, in response to the people's expectations of the Kingdom of God appearing immediately. (Luke 19:11)
When Jesus enters Jerusalem, there is a great deal of confusion on this matter - the people are all hailing him as the coming King:
“Blessed is the king who comes in the name of the Lord!”
“Peace in heaven and glory in the highest!” (Luke 19:38)
Matthew and John remark on the crowd cutting down palm branches (Matthew 21:8; John 12:13), which is uncharacteristic for Passover. It is likely the people are invoking some of the Messianic patterns from the previous 2-3 centuries during the Maccabean revolts, which had resulted in palm branches being published upon coins as marks of national victory:
Tabernacles came to be tied to Jewish hopes for a Davidic messiah and national independence. Judas Maccabees used the feast as a model for his celebration of the rededication of the Jerusalem altar in 164 B.C.E. (1 Macc. 4:54-59), the first celebration of Hannukah (2 Macc. 1:1-36). Elements of the Tabernacles celebration figure in Jesus' triumphal entry and crucifixion (Mark 11:1-11 par.), reflecting the people's longing for Jewish independence (cf. quotation from the Great Hallel, Ps. 118:25-26; the title Son of David, Matt. 21:9). The leaders of both Jewish revolts against Rome (66-70 and 132-135 C.E.) also used symbols and slogans from the feast.
David Noel Freedman, Allen C. Myers, Eerdmans Dictionary of the Bible.
The crowd perceives Jesus' coming to Jerusalem as an uprising, similar to the Maccabean revolt.
Jesus' Response to the Triumphal Entry
In all four Gospels, Jesus responds to this situation in advance, preventing the crowd from completely controlling the narrative - he's here to bring salvation, but not a military victory. Matthew and John explain that the colt Jesus rode was foretold in Zechariah 9:9.
Rejoice greatly, O daughter of Zion!
Shout aloud, O daughter of Jerusalem!
Behold, your king is coming to you;
righteous and having salvation is he,
humble and mounted on a donkey,
on a colt, the foal of a donkey.
Zechariah's next verse (9:10) expounds on this event as being one of peace, where the implements of war are no longer relevant:
I will cut off the chariot from Ephraim
and the war horse from Jerusalem;
and the battle bow shall be cut off,
and he shall speak peace to the nations;
his rule shall be from sea to sea,
and from the River to the ends of the earth.
We can see that Jesus is clearly taking pro-active control of the narrative in this situation, and challenging the militaristic preconceptions of the crowd.
Introducing the Nobleman
Similarly, Jesus invokes this specific historic context in this rendition of the parable to challenge the people's perceptions. He begins the story as if it is one the people are very familiar with:
“A man of noble birth went to a distant country to have himself appointed king and then to return. So he called ten of his servants and gave them ten minas. ‘Put this money to work,’ he said, ‘until I come back.’ “But his subjects hated him and sent a delegation after him to say, ‘We don’t want this man to be our king.’" (Luke 19:12-14)
The people understand the reference, they smile and they nod - they remember this story well. Jewish kings never needed to go and 'have themselves appointed' - this is what the Herods did. Herod the Great, Antipas and Archelaus all attempted this, and the latter had a Jewish delegation which followed him, as happens in Jesus' parable. And the delegation were successful in preventing Archelaus from becoming king.
So the lines are drawn - initially, the people would assume that the nobleman is the bad guy and the delegation are the good guys of the story. But then comes the plot twist: the nobleman becomes king.
Our own biases are invisible until confronted
Everybody suffers from Confirmation Bias - we tend to frame all new information in a way that reinforces our prior beliefs. Jesus is intentionally injecting conflicting ideas to force people to think harder about what he is teaching, as he does in the Prodigal Son, the Good Samaritan and other parables. Jesus is doing what all excellent teachers do - shaping the teaching to be most effective in that particular moment to his particular audience.
By framing his hearers as the bad guys in his parable (including killing them at the end, v27) Jesus forces them to re-evaluate their standing with him. No more smiles and nods. Their choice is to either be the bad guys, or else those entrusted by the nobleman to 'do business' in a land hostile to their own coming King.
Without this reference to Herod Archelaus, the audience's assumption would be that they are the nobleman's trusted servants in a hostile Roman land, awaiting their coming Messiah - that's what they already think. By beginning with this pointed political moment, Jesus changes the starting assumption, helping them digest the parable properly.
And don't forget the Sequel
Jesus is also setting up for his next Parable, The Parable of the Tenants (Luke 20:9-19), which draws on very similar ideas and explicitly pits a vineyard owner (invoking Isaiah 5:1-7) against violent and disobedient tenants, again representing the Jewish leaders. In the sequence of passages across Luke 19-20 there are repeated messages confronting the crowd's political (and spiritual) biases in light of Jesus' teachings.