The municipality's name has varied in spelling over time, with the forms Hohlonich, Holonich, Hohlemich, Hohlnich, Kollnig, Holineych, Hulnich and finally Hollnich all known to history.

Interpretations range from the designation of a settlement bei der hohlen Eiche (“by the hollow oak”) with unreliable secretaries then corrupting the spelling, to a Germanic-Celtic placename with a typical —ig ending.

[3] In 1310, Hollnich had its first documentary mention, along with several local fiefs, in the Sponheimisches Gefälleregister, a taxation register kept by the County of Sponheim.

From October 1794 to 1 January 1814, Hollnich belonged to the Department of Rhin-et-Moselle, the Arrondissement of Simmern, the Canton of Kastellaun and the Mairie (“Mayoralty”) of Gödenroth.

It never seemed to hold very much importance, as witnessed by the dearth of records that mention it, although a reference from 1672 states that the estate was earning the clergyman at Kastellaun income from land tenancy and oats.

The buyer was a one Johann Friedrich Hildenbrand from Bacharach, whose great plans, not only for farming there but also for building a linen and cotton factory, as well as a brandy distillery, all fell through.

Proceedings in Roth on that day put it to the council that an agreement with Hollnich's mayor on 19 April 1939 had amounted to amalgamation.

The municipality's arms might in English heraldic language be described thus: Or a bend sinister countercompony argent and gules issuant from which a lion rampant guardant of the third crowned azure, and below which a bush of the third.

The “bend sinister countercompony” (diagonal chequered stripe) is inspired by the “chequy” arms borne by the Counts of Sponheim, who held the low court jurisdiction in Hollnich, but it stands first and foremost for the outlying centre of Gammelshausen, which in ecclesiastical history was attached to the Sponheim holding of Kastellaun through a property that the Kastellaun church owned there.

The following are listed buildings or sites in Rhineland-Palatinate’s Directory of Cultural Monuments:[7] Hollnich is a good starting point for outings, with ideal connections with hiking and cycle paths, including the nearby Schinderhannes-Radweg.

Agriculture, once the mainstay of the local people's livelihood, nowadays counts only two full-time operations and fewer than five more that work the fields as a secondary income earner.

Since the outlying centre of Rothenbusch came into being, the number of white-collar and public-sector workers living in the municipality has risen sharply.