The plan was for a two-week trip, commissioned by donors, when I landed in northern Iraq one day in June. Foremost on my mind was finding Christians, specifically evangelicals, who remained in spite of attempts by ISIS to drive them from their homes, especially during its three-year reign of rage from the city of Mosul.

Although I did not know it, the biggest impression made by meeting these Christians would be their linkage between today's Middle East geopolitics and the ancient empires of Assyria and Babylon.

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I was also curious about two other things: were there any Jewish footprints left in the land? At the turn of the 20th century, Jews were the single largest ethnic group living in the area now called Iraq. Today there are virtually none.

And what about reports that Kurds, almost entirely Muslim, felt an affinity with Israel? Did they? Was it true?

Making my way from Jerusalem to Amman (a story unto itself), I flew out from Queen Alia Airport on a two-hour flight to the 7,000 year-old city of Erbil.

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A 15-minute taxi ride from Erbil's airport took me to the house where I would take my stay. Occupied entirely by journalists, it was a temporary home that quickly helped me see that in spite of familiarity with the politics and maneuverings of Tehran, Baghdad, Damascus, Ankara, Moscow and Beijing, I knew next to nothing about the region's heart... which is to say, I knew almost nothing about the ancient roots of Christianity there and the even older roots of the Kurdish people.

My first lesson was the meaningful difference between Iraqi Kurdistan and the nation of Iraq. In fact, Iraqi Kurdistan is almost a country unto itself. It issues its own visas, and has fairly well-defined borders separating it from Baghdad's day-to-day governance. Erbil, about 226 miles north of Baghdad, is its capital, where it keeps its own parliament and ministry offices.

A sprawling metropolis of more than one million people, Erbil is a melting pot of business, refugees, diplomats and a mix of Kurds from the several countries where they are found.

Although it is the most visible Kurdish governing authority, Iraqi Kurdistan is only one part of Kurdistan at-large, a distinct geographical and cultural area that includes portions of Syria, Turkey, Iraq and Iran. Enveloped by the Ottoman Empire and artificially carved into parts of separate nation-states in the aftermath of the First World War, today's Kurds, somewhat like Jews, retain a distinct ethnic and cultural identity that defies their history.

After learning how little I knew about the place I came to see, I hunkered down and studied. In addition to meeting with people to help me learn, I also settled into They Say We Are Infidels: On the Run from ISIS with Persecuted Christians in the Middle East, a book by journalist Mindy Belz.

Duly informed, if only at a beginner's level, I extended my stay from two weeks to four, rented a car and set out to explore.

Dodging potholes that could swallow a truck, I made my way both west and south. To the west, I visited Nahum's tomb in Alqosh. Nahum is a largely unknown biblical prophet who in the late seventh century BC, foretold God's judgment on Nineveh, heart of the notoriously cruel Assyrian Empire.

"Woe to the bloody city," Nahum cried in the name of the God of Abraham, Isaac and Israel. "You are overflowing with lies, pillage; and bodies, countless bodies. As you have done to victims, I will lift up your skirts over your face, throw dung on you, make you vile. When word of your destruction is made known, the entire world will applaud" (a paraphrase from Nahum, Chapter 3).

There probably are other Jewish footprints in Iraqi Kurdistan, but the tomb of Nahum was the only distinguishable one I could find.

In the city of Zakho, only a few minutes from Syria and Turkey, I found the Khabur River where the exiles of Israel were taken in 722 BC, but found no trace of anything Jewish in what was the city's Jewish quarter only 100 years ago. On my way back to Erbil, I also stopped at the village of Al-Shikhan, where I was told there had been a Jewish cemetery that was now part of an Arab-Islamic one. Finding the place, there were marker nubs, but nothing left that indicated Jews had lived and died there.

It was in Sulaymaniyah, a mere 30 miles from Iran's western border, that I finally found two graves said to be Jews by Kurds who now live in that city's old Jewish quarter. With unmarked headstones hidden behind a metal door, I propped the door open, found two stones, and placed them on the top of each marker.

After putting photos of the graves on Facebook, an Iranian Kurd recently retired from the Peshmerga military immediately called, urging me to take down the posts until I was safely back in Erbil or, better yet, Israel.

"There are Iranian IRGC spies in Sulaymaniyah," he warned. "If they see your post and think that you are Jewish, it would not be good for you."

I took his advice and deleted the photos, reposting them only after I was back in Jerusalem.

Security is a big concern for everyone I encountered. Posting photos with faces or identifying anyone by name is a taboo about which visitors are regularly warned -- and for good reason.

In spite of putting up my guard while there, I became friends with an Iranian Kurd living in exile from his family. He spoke impeccable English, and had a manner that reminded me of one of my sons.

Because today's Kurds are found in Iran, Iraq, Syria and Turkey, there are countless interactions between them. Infiltrating enemy strongholds in countries outside its sovereign reach, Iran of course recruits susceptible Kurds to gain intelligence. To the degree they are not already doing so, the US and Israel would be wise to follow suit. In all likelihood, they are. It just makes sense.

Before arriving in Erbil, the dynamics I had missed, the stories I did not know, were about the Kurds and Christians who are part and parcel of the ancient landscape -- and today's complicated realities.

Why do Kurds, overwhelmingly Muslim, find it easy to ally with those who do not share their religion? Kurdish leaders with whom I met, including Khalid Jamal Alber, the KRG's director-general of Christian affairs, made the answer clear. Unlike the Islamic population in the Palestinian territories, their unifying identity is political, not religious. First and foremost, they are Kurds. All who stand with them are friends -- including Israel.

As for Christians who remain, refusing to leave?

"We stay because we see a direct connection between Saddam and Babylon, ISIS and Nineveh," one evangelical pastor told me over coffee. "Like Babylon's Nebuchadnezzar, Saddam set out to make himself equal to the ancient monarch. And just like Assyrians who impaled victims, relishing the horror they incited, so too ISIS made its headquarters in that empire's capital city, finding inspiration there.

"There are spiritual forces that cross the millennia," he explained. "We stay because they must be named, and they must be fought. No matter the cost, and especially in days like these."