The vast possibilities of the Great West caught his attention and he hastened to grasp his opportunities.  At St. Peter, in Minnesota, he was welcomed and resolved to locate.  They needed such men as Mr. Lothrop to help build the new town into a city.  The opening of the St. Peter store was characteristic of its young proprietor.

The extreme cold of October and November, 1856, prevented, by the early freezing of the Upper Mississippi, the arrival of his goods.  Having contracted with the St. Peter company to erect a building, and open his store on the first day of December, Mr. Lothrop, thinking that the goods might have come as far as some landing place below St. Paul, went down several hundred miles along the shore visiting the different landing places.  Failing to find them he bought the entire closing-out stock of a drug store at St. Paul, and other goods necessary to a complete fitting of his store, had them loaded, and with several large teams started for St. Peter.  The same day a blinding snow storm set in, making it extremely difficult to find the right road, or indeed any road at all, so that five days were spent in making a journey that in good weather could have been accomplished in two.  When within a mile of St. Peter the Minnesota river was to be crossed, and it was feared the ice would not bear the heavy teams; all was unloaded and moved on small sledges across the river, and the drug store was opened on the day agreed upon.  The papers of that section made special mention of this achievement, saying that it deserved honorable record, and that with such business enterprise the prosperity of Minnesota Valley was assured.

He afterwards opened a banking house in St. Peter, of which his uncle, Dr. Jeremiah Horne, was cashier; and in the book and drug store he placed one of his clerks from the East, Mr. B.F.  Paul, who is now one of the wealthiest men of the Minnesota Valley.  He also established two other stores in the same section of country.

Various elements of good generalship came into play during Mr. Lothrop’s occupancy of this new field, not only in directing his extensive business combinations in prosperous times, but in guiding all his interests through the financial panic of 1857 and 1858.  By the failure of other houses and the change of capital from St. Peter to St. Paul, Mr. Lothrop was a heavy loser, but by incessant labor and foresight he squarely met each complication, promptly paid each liability in full.  But now he broke in health.  The strain upon him had been intense, and when all was well the tension relaxed, and making his accustomed visit East to attend to his business interests in New England, without allowing himself the required rest, the change of climate, together with heavy colds taken on the journey, resulted in congestion of the lungs, and prostration.  Dr. Bowditch, after examination, said that the young merchant had been doing the work of twenty years in ten.  Under his treatment Mr. Lothrop so far recovered that he was able to take a trip to Florida, where the needed rest restored his health.