He learned quickly to understand and speak Swedish, and as consul, in the kingdom of Sweden-Norway he laid plans for a large emigration of both Swedes and Norwegians, with the hopes that most would seek new fortunes in his home state of Maine.

As he wrote April 5, 1864, for the encouragement of immigration: "Besides all other reasons, I believe these honest, pious, plodding Swedes would form an excellent balance to the fickle, merry, light-hearted Irish, who are now crowding in such goodly numbers to our shores."

In every hamlet where I pass the night, at every post-station where I await fresh horses, I shall scatter such information as I have found by experience to be best calculated to promote the emigration of these Scandinavians to our own land.

It is my intention on my return to report the results of my expedition to the Department, giving special attention to the subject of immigration, stating what impediments still exist, and the best means of overcoming them.

Towards the end of June 1865, he set out on the journey he had planned, taking with him the text of the Homestead Act and other documents printed in the language of the country, proposing to sow this good seed broadcast all along his way.

Returning to Gothenburg after several months, he sent his report to the Department of State, an excerpt of it reads: One of the chief objects of my expedition was to diffuse knowledge tending towards emigration, and whether driving over the fjelds, scaling mountains, resting at stations, or coasting along the shore in steamers, I everywhere preached an immigration crusade to the laborer's paradise in the New World.

I spoke of our homestead law — the fertility of our soil — the length of our summer — the richness of our immense mining districts, but I found nothing so telling as the simple description of the condition and prospects of the working man in the United States of America.

Of fifty odd postillions I had along the road, all promised me to immigrate to the United States next Spring, save one; he, I ascertained, had been in England for nine months, and, judging all foreign countries by the one he had visited, concluded, perhaps wisely according to his light, to remain at home.

In no case did one discussion descend to altercation, and no unfriendly words were ever used.Thomas estimated a total of 10,000 immigrants that year to the United States from Sweden and Norway, but he was quick to add the numbers would prove rather under than over the truth.

He continued, "in this conviction of peace, lies the greatest hope for every friend of Scandinavia, that the union between these two noble nations in the high north, must be preserved in one form or another."

Thomas' last mission as American Minister ended that spring; he was recalled on May 31, making him in effect the last US ambassador to the united kingdoms of Sweden and Norway.

[6] His wives were the daughters of Dr Henrik Ragnar Törnebladh (1833–1912), a headmaster and member of the Swedish Parliament 1873–1875, 1879–1888 and 1889–1909, and his wife Elisabeth Maria Siljeström (1842–1929).