Regardless of how they spell their particular version of surname, most family members are aware that it is a nickname which means "Sweet Milk" in English. In a Bohemian surname origin book (Nase Príjmení by Dobrava Moldanová, published in Prague in 1983) the name "Sismilich" is found, coming from the German name Süsse Milch = sladké mléko, or sweet milk. Thus, the name is recognized as being a Bohemian family name, but of German origin. The family name originated long ago, and probably referred to a dairy farmer whose fresh milk had a particularly sweet taste. In a couple of widely separated branches of the family, tradition has it that the milk came from goats, which are supposed to produce particularly sweet-tasting milk, rather than from cows. One version of the family crest is reputed to incorporate the head of a ram.

Only about 10% of Western surnames are nicknames (other examples are Stout, Goodman, Longfellow). Most surnames are place names (43%, eg. Brooke), patronymics (32%, eg. Robertson), or occupational (15%, eg. Smith). Ours is not a nickname that was ever widely used; at any time and place in history where varieties of the surname are found, there are never a large number of people who possess it. Therefore, the current belief is that, unlike a surname such as Smith which was independently given to a large number of unrelated persons, our surname began with a single dairy farmer or a family of dairy farmers, and the surname then spread as families migrated over the succeeding centuries throughout the countries of Europe, and in the 19th and 20th centuries, to North America, Australia, and New Zealand.

Recent evidence points to that first ancestor being a Norwegian Viking who lived some time prior to 1000 AD. The earliest known mention of the family surname is for a Swetmilk in York, England, in the year 1120. Also, a Peter Swetemilk appears in the "Calendar of Inquisition Post Mortem" in Yorkshire a century later, in 1258. From the year 866 until 954, York was under the control of Norse Viking rulers. The original spelling of the surname was most likely as Sotmelk; searching the web for this name today will yield only sites in Norway.

Lending further support to Viking origins are the subsequent appearances of Sweet Milks in European towns associated with the Hanseatic League, an association of medieval north German cities formed to advance their common commercial interests. It began in the late 1100's after the Holy Roman Emperors became weaker and could no longer protect the cities. The league checked piracy on the Baltic and North seas, defended participants against aggressors, promulgated commercial laws, prepared charts and navigational aids, and won concessions for its merchants. At its peak from 1350 to 1500, over 200 cities were members.

Based on the timing of the appearance of the surname in other European cities along the Hanseatic Route, it is likely that the next migration for family members was to Belgium. Johannis Zoetemelkes appears in Aalst, in the year 1240, followed by Kerstienne Zoetemelc in Ieper (also known as Ypres) in 1306, and Willemme Soetemelc in Ghent in 1337. After this, a branch migrated to Poland, with a Susemilch and a Zawirmilch living in Breslau (modern-day Wroclaw) in 1345. Breslau was a major trade center on the route between southern Europe and the Baltic Sea, the capital of Silesia in the 12th century, and ruled by Bohemia during the time the Sweet Milks first arrived there.

Moving forward into the mid-15th century, a branch of the family migrated to the Bohemian Lausitz, a region located where the Czech Republic (Bohemia), Germany (Saxony), and Poland (Silesia) come together today. It is uncertain, however, where this branch migrated from. The patriarch of the Lausitz branch is Jacuf Sussmilch, who was mayor in Pirna, a town in Saxony, in 1453. One of his descendants, Bartholomaus Sussmilch, was born in Pirna, and by 1513 had moved to Tolstejn (also known as Tollenstein), in Bohemia. He was a hereditary Judge, and of considerable note is that he was the owner of the Tolstejn Castle, the ruins of which still exist today on a hill in Tolstejn and have been visited by several family members during the 1990's.

It is believed that Bartholomaus is the common ancestor of the majority of the Sweet Milk family members known to us today. The descendants of Bartholomaus' son Andreas remained in Tolstejn for at least 6 additional generations. Family members from this branch still remain in the Lausitz portion of the Czech Republic today. This branch likely includes the Sismilich families in Litomerice, Bohemia. Bartholomaus himself migrated to Leipzig, further to the west in Saxony. The descendents of Bartholomaus' son Barthel populated many other towns in Saxony, including Freiberg, Coswig, and Bischofswerda. Descendants of Barthel still live in the city of Dresden today.

Other considerations than lend credence to our Norwegian Viking origins are a number of Viking given names to German family members in the 1600's (for example, Hajo and Johannsen, or son of Johann). Also, Norwegians were known to be merchants or involved in the law, and many of the early Sweet Milks were merchants or were involved in town administration, such as Jacuf and Bartholomaus.

Early in the 17th Century, the migration pattern becomes murkier, as it most likely becomes entangled with the religious strife of the Protestant Reformation which culminated in the Thirty Years War (1618-1648). Saxony had become a stronghold of the followers of Luther, while Bohemia officially remained Catholic and supported the Holy Roman Emperor. The oral tradition in many different family branches lend support to the proposition that Protestant family members migrated to Germany, including Berlin, around this time, and Catholic ones to Bohemia, including Prague. One German branch of the family might have migrated during this time to the Hanover area - Gosler, Lehrbach, and Osteroder, where Suessmilch's have been from at least the 1700's up until the present day. Even today, the descendants of the German Sweet Milk families tend to be Protestant, while those of the Czech branches tend to be Roman Catholic. One of the casualties of this era appears to be the change of the spelling of the family name in Bohemia to the Czech version, Sismilich, a small reflection of the hostility to things German in Bohemia at that time, some of which still continues to the present day in the aftermath of World War II.

Later in the 17th Century family members appear in several new countries: Denmark (Paulus Susemihl in Naestved in 1639), the Netherlands (Jan Jacobsz Zoetemelk in Lekkerkerk in 1660), and France (Johann Ernst Susemihl in Nieder Rodern in 1668).

A major Catholic branch of the family emerged in 1777 in the hamlet of Klisinec in southern Bohemia, about 40 miles south of Prague. The patriarch of this branch is Jan Jirik Sismilich, a stonecutter, who moved to the area with his wife Anna, who was from Prague. While it is not yet clear, Jan Jirik may have been accompanied to the area by two other family members, possibly his brothers. Jan Jirik had two sons, Josef and Frantisek. The head of another branch from Klisinec is also Josef Susmilich. There is a good chance that this Josef was Jan Jirik's son, and this is a current topic of research that would tie two US families consisting, together, of approximately 150 people with the family names Susmilch and Sismilich together. Both Frantisek's son and four of Josef's sons, all of whom were also stone-cutters, independently emigrated to the United States in 1868, settling in different areas. At least one other Bohemian, Franz Josef Sismilich, came to the US in the 1890's, and a number of his descendents are also known today.

These three Bohemian branches are predated in the United States, however, by the family of Dr. Friedrich Ludwig von Suessmilch, who arrived in New York from Wurzen (adjacent to Leipzig) in 1847, went to Milwaukee, then settled in Delavan, Wisconsin. Dr. von Suessmilch is likely a member of the Bartel branch in Saxony. But undoubtedly the first family member to migrate to what would eventually become the US was a Swetemelk who came to New Amsterdam (New York) in the mid-1600's on board the Dutch ship "De Bonte Koe" ("The Spotted Cow").

A branch of the family led by Bernhardt Robert Sussmilch migrated from Germany to England, and in 1909 moved on again to New Zealand. One of the versions of the family coat of arms and crest were passed down through this branch. This family continues to grow in New Zealand today.

Another German branch of the family, but with Bohemian roots from Samuel Anton Sussmilch in the mid-1700's, migrated from Hamburg to Australia in the early to middle years of the 19th century. From this branch came Adolf Carl von der Heyde Sussmilch, who gained fame as a scientist who was involved in developing methods of technical education.

Yet another branch of Sweet Milks migrated to Argentina in the 1880's.

The following list shows the many different versions of the Sweet Milk name that have been found over the centuries in different languages:

English: Swetemelk - Swetmelk - Swetmilk - Swetemilk - Sweetmilk

Belgian: Soetemelc - Zoetemelc - Zoetemelkes

Dutch: Zwoetemelk - Zoetemelk - Soetemelk

German: Sotemelk - Sussmilch - Susmilch - Suessmilch - Sussemilch - Sussmilck - Sussmilk - Suszemilch - Seussemilch - Sussenmilch - Suesmilche - Suessenmilch - Susemihl - Susemiel - Susemuhl - Susemyl - Susemule - Susemill - Zuzemelch

Czech: Sismilich - Sismilick - Sismelich

Polish: Susmelh - Susmelch - Zawirmilch