Eagle Pencils was established in New York in 1856.  Ross wrote:  "I have been getting a lot of information on penpoints from a wonderful book called  La m*moire des Sergent-Major , by Jean-Pierre Lacroux & Lionel Van Cleem.   This book--219 pages--has hundreds of beautiful, colored illustrations of nibs, nib boxes, etc., and is full of useful information on the history of penpoints. (Unfortunately the book is also full of typos and factual errors.)

"Henry Berolzheimer did not found the company in 1856.  He took over the family business in 1861."  [Gwin note: i.e., Henry did not start it then, but the Berolzheimer family did--likely Henry's father?  In 1894, Young states,  Eagle opened its London office,  in 1931 it opened a factory in Canada, and in 1949 it opened a factory in Mexico.  The New York factory and offices were closed in 1958]   Ross continues: "Henry Petroski  (The Pencil, page 174) writes:  'The family continued to control the company well into the twentieth century, but in recent years [Young agrees: 1969] Eagle was renamed, after the family's Americanized name.  The Berol Company in America continued to be known as Berol USA even after it was in fact owned  [Young says Empire acquired Berol in  1987] by the Empire Pencil Company of Shelbyville, Tennessee, which in turn was owned by the Empire Berol Corporation, which was acquired in 1988 by a New York investment group.' "

"Eagle purchased Venus in 1971 (not the other way around), and changed its name to Berol then. Did the Eagle Pencil Co. really make nibs?   Yes, I believe they did, because: 

(a) they manufactured pencils, penholders, pencil sharpeners, and other goods related to writing (i.e., they had a large, efficient factory); and  (b) the dozen or so different nibs I've seen from Eagle do not appear to be clones."

And, as usual, Ross was right, as evidenced by this box I acquired (pictured above, 6" x 8" x 1 7/8"), the original contents of which were a half gross of their #300 Reporter Pencils, according to the end label.    On it  is a picture of the "new" Block Long Factory, New York, which Eagle built and into which it moved in 1900 [Young]. 

The sign on the near building's face identifies the site and advertises the London office: " Eagle Pencil Company's Works   -   Office & Salesroom  -  703 East 13th Street  -  Tottenham, London, N., England". 
In addition, each of the various buildings in the compound is labeled, respectively:  "Graphite Works", "Pen & Pencil Cases and Rubber Works" [Eagle made the world's first eraser-tipped pencil in 1872, according  to Young], and on the far side, as Ross predicted, "Steel Pen Works".
 

But now the question arises as to when Eagle began  producing pens.  We know Esterbrook was first in 1858, so it had to be after that.   Was it before 1900 (in the first New York factory) or only afterward in the new plant?   And for how long were they produced?  A packing slip I found in a box of NOS Eagle nibs was dated January  1948, so I know they were producing at least until then.   Could it have been right up to the 1958 closure of the New York factory?  Do you have some additional documented information that can help?